The criteria I have used to make my selections is (admittedly) subjective—but in general, I favor only those races that were shown in the movies or that were very prominent in the expanded universe (comics, novels, video games, the RPG, etc.). There are a few races I chose simply because I like them a lot. But then, It's my list, so... nyah. Please note that these races are not the most 'common' in the Star Wars galaxy, rather, they are the most 'visually archetypical' to the setting as a whole.
We'll start with the most 'important' races first (those featured prominently in the movies—characters with actual lines and names):
Aqualish — aka Walrus Man. He picked on poor luke and lost an arm for his troubles
Besalisk — The four-armed short-order cook. Friends with Obi-Wan in Episode II
Clawdite — The cute bounty-hunter chick (from Ep II) who turned into some kind of big lizard! (Don't they always?)
Dug — The hand-walking, mean-spirited pod-racer from Ep I. Poo-Doo!
Ewok — Killer teddybears. Love 'em or hate 'em, they're memorable.
Gamorrean — Space orcs! Who doesn't love drooling space orcs.
Geonosian — Bug-men from Ep II.
Gungan — Jar-Jar may give them a bad name, but you got to give them some credit for attacking tanks and droids with electric blue-balls.
Human — Duh. Some of them look good in gold bikinis.
Hutt — Bloated slugs. They do NOT look good in gold bikinis (but like humans who do).
Jawa — Oo-Tee-Nee! Rodent-like droid-salesmen.
Kaminoan — Very cordial, but wouldn't want those long necks anywhere near a lightsaber.
Kubaz — Long-snoot the spy. He sold out to 'the man'.
Mon Calamari — Delicious with butter. Prone to falling into TRAPS! Like their coffee hot.
Neimoidian — The cowardly operators of the Trade Federation. Racial stereotype or just interstellar scumbags? You be the judge!
Rodian — Oo-Ta-Goo-Ta, Solo? Bug-eyed little green men with antennae. Don't always make the best judgements regarding Corellian smugglers.
Sullustan — You know, lando's co-pilot from RotJ. And...that's about it.
Toydarian — Heh, I liked the little pot-bellied little humming-bird man with a tapir snout. He shouldn't gamble, though.
Wookiee — Arroooooo! Big. Hairy. Good to lean against. Affectionate.
Zabrak — One bad apple spoils the bunch. Darth Maul was one bad apple.
Now, the next group of races are mainly those who appeared in the movies, but didn't have real speaking parts. Plus, there are a couple who only became popular through novels/comics.
Bith — The guys in the cantina band. Probably one of the most recognizable symbols of the movies.
Bothan — Fey'lya. Annoying, furry, self-serving politicians. (Well, aren't they all?)
Chiss — Grand Admiral Thrawn. For some reason, being blue-skinned and having red eyes supposedly makes you cooler.
Falleen — Prince Xisor. "sexy" lizard-people with pheromones. Man, he almost got himself some Princess Leia...but.. DENIED.
Gand — Zuckuss. Freaky bug-headed bounty hunter. Partnered with a freaky, bug-headed droid. Go figure.
Trandoshan — Big lizard dudes who hate Wookiees— and shoes apparently. We don't need their scum.
Tusken — Sand People! Utt-utt-utt! They always ride single file, to hide their numbers.
Twi'lek — What is it about tentacles that makes a woman so sexy. Or not.
Ugnaught — Little pig-men. Hell, every movie had to have one race of short guys. This was them in ESB.
These are the guys who only show up briefly in the movies or who have minor parts in big books or big parts in minor books. It also includes a few of my own selfish choices of races I have a fondness for.
Abyssin — The one-eyed guy in the Cantina. Oh, and his kind regenerates. Handy.
Arcona — One of the first guys you see in the Cantina, the triangle/snake-headed guy who pops up into screen. Addicted to salt? Aren't we all.
Arkanian — Humans, but somehow cooler because they have white hair...and no pupils in their eyes. Creepy.
Askajians — You may not WANT to remember her, but you probably do. You know, the fat, multi-breasted 'dancer' waddling around Jabbas palace. A contrasting counterpoint to the much more pleasing 'Oola the Twi'lek'
Balosar — You want to buy a death-stick? No? Well, I'll go re-examine my life. Humans with antennae and bad habits.
Barabel — Some kind of big lizard!
Bimm — Hobbits... In... Spaaaaaace! Or at least they were until someone drew them with long snouts and big, pointy ears. Probably he same guy who drew Bothans with long snouts and big pointy ears. Dude. Seriously, I like dogs too, but... come on.
Cathar — Okay, so maybe Juhani from KotOR was an annoying character, but the idea of cat-people is still cool.
Cerean — They are coneheads. They are from France.
Chandra-Fan — Cute little mouse-bat people. Awwww, look, she wants a drink from the bar!
Chagrian — What is it with aliens with head-tentacles? And this guy has horns growing out of them. Wow!
Coynite — Lets see. A culture of war-like humanoids with ridged-heads and a strict sense of honor. Klingons, off the port bow!
Defel — Short little wolfy-dudes who's fur absorbs light, making them appear 'wraithlike'. Cool concept much abused by many gamers, I suspect.
Devaronian — A human guy with red skin and horns? Wonder how they came up with the name...
Duros — I don't know why, but I like this race. Maybe it's because they kind-of look like 'Grey' aliens—big heads, featureless faces, big eyes. Yes, just like the ones who abducted me.
Etti — Skinny, frail near humans. But mentioned in the Han Solo trilogy, so they get 'cool' points just for that.
Givin — Walking skeletons. Another cantina dweller. Pretty sweet that their exoskeleton can function as a space-suit (for a while, anyway).
Gotal — One of two goat-like humanoids. Flat-faced, with horns. Cool because they have a kind of precognition.
Gran — The OTHER goat-like humanoid race. They don't have horns, but they do have a muzzle—and three eyes. Must live near the nuclear power plant.
Hapan — Humans. Only they're all attractive. Oh, and they have a royal family.
Herglic — Walking whale-men. Awesome!
Iktotchi — They look kind-of like the bad-guy from "Legend"—reddish skin and horns. Only their horns are turned downwards, which is obviously less 'evil'.
Iotran — An interesting race taken solely from the RPG. Look 'em up.
Ishi Tib — Parrot-beaked fish-men! I always imagine them wearing eye-patches and pea-coats, with a corn-cob pipe in their beaks and a parrot on their shoulders. I don't know why.
Iskalonian — Fish-men! Kinda like mermaids, only cooler because they have legs. Otherwise, I mean.. what's the point? This was taken directly from the Marvel comics.
Ithorian — Hammerhead. Loved his action figure, and the race turned out to be cool, too.
Kaleesh — Though we never see one as a non-cyborg, still an interesting race (this is what General Grievous was before his 'operation').
Kallidahin (Polis Massan) — Short, gangly, featureless guys who couldn't talk. If so...then why did their midwife-droids?
Kel Dor — Freaky crested heads and breath-masks.
Kitonak — One of the (many) alien races from the Max Reebo band. This was the pear-shaped clarinet player.
Klatooinian — One of the various bumpy-face henchman races of Jabba the Hutt. Part of the whole 'Day the Earth Stood Still' in-joke about Klatuu Barada Nikto.
Lafrarian — Another race from the Han Solo trilogy. Humanoids descended from birds. Made good pilots. Go figure. Caw caw!
Lannik — Remember the big-eared, scar-faced midget-dude Jedi seen in Episode I? No? Well, he was a Lannik.
Lorrdian — Yet ANOTHER cool race from the Han Solo trilogy. A dark-skinned (PC: African-Amer.. no, wait.. Afro-Galaxian.. no.. ummm.. Black?) human species who are natural mimics. One of them (Fiolla) was a love interest for Han Solo. I now picture her as a Halle Berry type. Rrrowr.
Mustafarian — Not to be confused with a Rastafarian. These were insect-lookin' dudes who rode giant Fleas over beds of molten lava. No. Seriously.
Muun — Humanoid dudes with unsettlingly tall and skinny heads. Make you think the horizontal hold on your screen is off. Oh, they're Bankers. Yes, the 'Munn' handly 'Money'. Get it?
Nautolan — More tentacle headed dudes? Seriously? Well, this one seemed to be a Jedi with a sense of humor. At least he cracked a smile once. That's something.
Nikto — Another bumpy-faced henchman race of Jabba. Another part of the Klatuu-Barada-Nikto joke.
Noghri — The poster-child for unbalanced Star Wars mega races. Small grey guys who are very sneaky and complete badasses to boot. But...the're far too trusting.
Omwati — Another 'humanoid race descended from birds'. One of them was a top scientist who was romanced by Wedge Antilles.
Ortolan — Max Reebo! The Dr. Teeth of the Star Wars universe! Puffy, blue, elephant keyboard-player. Lak-ti-nep!
Pa'lowick — Sy Snootles! Where would Max Reebo be without his (former) lead singer! She was a giant, egg-shaped chick with spindly arms and legs and a trunk-like snout with creepy red lips at the end of it. Lak-ti-nep indeed!
Quarren — Squid-Face. That names suits them. Must suck to have the defining characteristic of your race be 'treacherous bastard'
Revwiens — An invention of West End Games. They're force-sensitive plants. Complete with leaf-like arms and legs and a mushroomish head. Cool.
Ruurian — The COOLEST race introduced in the Han Solo Novels (or at least the coolest character). Essentially a sentient caterpillar, about 3 feet long. They make good scholars and can occasionally outsmart the deadliest gunmen in the galaxy. Can't hold their liquor, but all kinds of awesome, otherwise (can you guess this was a personal pick of mine?)
Shawda Ubb — Another Max Reebo bandmember. A harmonica-playing frog dude. Careful, he can spit paralyzing poison! No. Seriously. Remember to tip your musicians.
Shistavanen — The wolf-man from the Star Wars cantina.
Skakoan — The creepy green-dudes with metallic voice boxes who were part of the 'Techno-Union'—and part of the Separatist movement in Episode III.
Sluissi — As far as I can tell, these snake-people were first introduced in the Thrawn novels by Timothy Zahn.
Snivvian — Snaggletooth. I used to love his action figure. Another cantina resident.
Squib — Short, blue-furred squirrel-dog-men who love junk and bargaining for junk. Introduced by West End Games. Love them.
Talz — ANOTHER Cantina resident. The big, white furred guy with four eyes.
Theelin — A late addition to this list, but one that it should not be without. This was a singer at Jabbas who was flirting with Boba Fett. That alone makes her memorable. The fact she has hooves only.. wait... gross.
Thisspiasian — Another snake man, only this one has a big bearded face. Literally, his whold face is covered with a beard. One of these guys was on the Jedi council.
Tiss'shar — Another from the Han Solo Trilogy. This was a lizard assassin type that has since been somewhat retconned to include a lot of 'velociraptor' influences. Kind of nice, actually. Fits. Oh and... Another big lizard!
Togorian — One of several 'Cat-people' races—this one introduced in the RPG.
Togruta — No. Seriously. ANOTHER hot female tentacle-headed species?
Trianii — Another 'Cat-people' race. Cooler background than the others since they came from the Han Solo trilogy (can you tell I liked that Trilogy?)
Tunroth — Hulking, beastial humanoids known for their hunting skills. Didn't stand out much for me until one of them joined Rogue Squadron.
Tynnan — Awwww! Cute little otter-people! And they came out YEARS before the copycat 'Selonians' and 'Drall' from the abysmal 'Corellian' novels.
Ubese — Leia disguises herself as one of these guys to get into Jabbas palace. They're essentially just humans anyway.
Umbaran — Creepy, bald-headed, manipulative and dark-loving species. Perfect henchperson for Palpatine during his rise to power.
Utapaun-Pau'an — Half of a symbiotic culture. The tall guys from Ep III who look like they have bark for skin.
Utapaun-Utai — The short little dudes who did all the work on Utapaun. Why? Because every Star Wars movie needs short dudes.
Vaathkree — Another from the RPG. Rock-like humanoids. I don't know why, but I love them—probably because they remind me of the Thing from the Fantastic Four.
Verpine — One of the best from the RPG. Gangly insect dudes. Made great comic relief.
Vurk — Another reptillian-humanoid species—this one with a big, crested head with eyes on either side. The only notable appearance in the movies was in Episode II. One of them (a Jedi) lept up to attack the Separatist leaders during the Arena battle. He was subsequently brutally gunned down by Jango Fett. I like to think they got the name of the race from the sound that guy made when he toppled off the balcony and hit the ground far below. Vurk.
Weequay — Yet ANOTHER of Jabba's wrinkle-faced henchman-species. These were the one with the dreadlock-like ponytails. Evidently, they taste real good to Sarlaccs. But then, they did look kind of like beef jerky.
Whipid — Big, tusk-faced furry dudes.
Yuzzem — Not to be confused with 'Yuzzum' (who came much later). YuzzEM are big, mean, furry-brutes. Like Chewbacca, only with big teeth and worse tempers. A pair f YuzzEM served as sidekicks for Luke and Leia in the Splinter of the Minds Eye book. I cried when they died. Sniff.
Yuzzum — Not to be confused with 'Yuzzem' (who are much cooler). I would not even have included these guys if not for the special edition movies. Here, they made the lead-singer of Max Reebo's band one of these guys—Joh Yowzah. Based upon this, this species should be known for abnormally large mouths.
Zeltron — An invention of the Marvel comic series. A race of attractive, near-human, magenta-skinned hedonists. What's not to like?
These are races that didn't make it mainly because I couldn't ever see a player WANTING to play one—or that they just plain aren't suited to being a PC race (unbalanced, too weak, too strong, too weird, etc.)
All those Pod Racer Dudes — Just me? or did all those guys look WAY too 'cartoony'.
Kowakkian — Salacious Crumb. Jabbas court jester and bane of C-3PO's eye.
Duinuogwuin — aka Star Dragons. Cool idea, but...100+ meters long? Kind of hard to fit in the typical YT-1300. Oh, that's right, they can fly through space without a ship.
Esoomian — An in-joke with my friends. This represents one of the most unbalanced 'twink' races there is. 7D strength indeed. Tantor SMASH!
Lepi — Sorry, Jaxxon. But I just couldn't bring myself to include giant, green, carnivorous humanoid rabbits.
Spiner — Same goes for giant porcupine-men
Ssi'ruuk — Velociraptors. Yawn.
Tof — Giant, fat, green space-pirates...who fly in space sailing-ships. No, not solar-sailers. Space Galleons. No. Seriously. Look it up.
Ugor — As much as I love the idea of space-suits filled with amorphous/tentacular blob-people who are fanatically religiously devoted to garbage...they would not make a good PC race—at least not as good as their arch-nemeses, the Squib
Wroonian — Seriously. How many blue-skinned near-human alien races do we need?
Zehethbra — Reference Lepi and Spiners above. Same goes for space-skunk-men.
Anyway, that's my list. Enjoy!