The nomadic Goliath tribes are the only beings with whom the Dwarves will trade on anything approaching a regular basis. Huge, powerfully built, and dotted with small, bony growths ("lithoderms", to be precise), they are about as hardy as they come. In wider society, they can gain some notoriety as soldiers and bodyguards, though most see them as "wild men", barbarians, etc. and their general representaion suffers for it. Some of the less tolerant cities lump them together with Orcs as "savages" - and, while there is little emnity between the two races, aside from the occasional scrap over territory and land, the Goliaths are certainly their own group.
Another rare sight on the continent (like Gnolls), Yuan-Ti are seen as savage, cruel warriors, and rarely tolerated for too long in human society. Those who do come to Delraith, however, are on a mission - they serve their God of Knowledge and Secrets, and look to collect as much information about the greater world as they can. Many take on a scholarly caste, but mix their natural strength and prowess in battle to become terrifyingly competent warriors, as well as masterful tacticians and living repositories of knowledge. Voted Race Most Likely To Accidentaly Unleash An Unspeakable Evil Upon The World.
Halflings are pretty much wee Humans - they're adaptable, they live in mostly the same places, and suffer little prejudice from the other races. While they're known to make great thieves, most keep on the right side of the law. Many come from agricultural backgrounds, like farmers or fishermen, and, while they rarely serve in the Guard or other armed forces, the odd few are seen - like Guard-Captain Tanis Dis, known for her shrewd cunning and great organisational skills. There are several myths regarding their origin, but most agree that they're just a smaller breed of human.
No Gnomes. Never liked 'em, and they tend to have a lot of crossover with Dwarves, Halflings, and Elves, depending on their angle. There might be one or two as NPCs, but they'll be servants of the Fey creatures of other worlds, or perhaps advisors to powerful Elves, but nothing more.
Then you have your monster races - not really PC options, but they'll show up.
Half-Dragons are the result of breeding between the god-like Dragons and lesser races. Dragons can reproduce with most creatures (note that they are never the parent who bears the child - Dragons do not breed with each other, and need to take the form of other races and help things along with magic to achieve conception).
The most common Half-Dragons are experiments, and are often malformed - but those who are sucessful can run the gamut from miniature Dragons, to full-blooded members of other races with the ability to shapechange, to those who have some Draconic characteristics (like claws, scales, or wings).
Valkrith, Red Terror of the East, is known to frequently breed with the Kobolds under his command, and most of the military leaders of his warriors are his own Half-Dragon spawn. They stand a full foot taller than most Kobolds, and have a build closer to a human than the spindly form of a Kobold. They possess a variety of traits from him (from wings, full claws, to one or two even being able to breathe fire), though only two have so far inherited his sorcerous ways - K'Lis, his second-in-command, and Va'Krin, his daughter, who has begun amassing her own army to overthrow Valkrith.
Lizardmen (or Scalefolk, as they are known) are a race of nomads and traders. Due to the only-just warm climate of Delraith, those who have come from warmer climes tend to spend their days lazing in the sun, attempting to regulate their body temperature as best they can. During the winter, many enter a state of suspended animation (called The Long Sleep, or the Half-Year Death). A few have been seen to be a lot more active, carrying mysterious stones that provide them with warmth (most often embedded in their chests). Many claim they have some secret link with the mighty Dragons, but so far nothing conclusive has been proven.
Draconic Creatures are the bizarre result of experiments by would-be Dragons (and some of the younger Dragons) into the Draconic Ascension process. They come in many wide and varied forms, with most bearing traits from the Dragon who spawned them. Anathraxiis' experiments are often black, sleek creatures with an affinity for water, while Sheelis, Green Horror of The Dire Woods, tends to spawn lithe, powerful near-human (or demi-human) creatures. A good source for ideas for these creatures is the D&D 3.5 Monster Manual IV, which deals with the "Spawn of Tiamat" - draconic creatures made from the corruption of dragon eggs, with their own particular habitats and tactics. Some are of animal intelligence (such as the Blackspawn Lurker), and some are weak (the Greenspawn Skirmisher), while others are formidible, intelligent foes (the Redspawn Arcaniss). Or, take another creature and add unusual abilities and Draconic traits to season (fire-breathing, magic-shooting, winged T-Rex, anyone?)
Each Draconic Creature should be unique - they are one-of-a-kind bendings of the rules of nature. They make great "minibosses" for dungeons, and it seems like a very Draconic plot to send a crack team of Kobolds out to some God-forsaken dungeon to clean up their Master's mess.
And the usual mess of Devils, Demons, and Undead that populate any good D&D setting. I like the idea that the Undead maybe come from one mythological event - say, an ancient Wizard, whose name was lost to time, who tried to cheat death - not just through ressurection, but by actively killing the God of Death. Well, as you might guess, the paradox inherent in that act led to a small break in reality - the Shattered Veil, or something similar, a overspill of Death into the world, which can result in naturally reanimated creatures. Many are made by evil Magic-Users, of course, but they tend more towards the "construct" feel and theme rather than beings like Vampires and Ghouls.
And there'll always be "edge cases" - a player who wants to play something weird, or a specific subrace of on of the existing races. I'm not a huge fan of 3.5's "We've got an Elf for that" ethos, but I might consider something like allowing Elves to have different stats and such according to their Court (to pluck from every other Fey-based Elf) - like, Summer to sub in for Sun Elves, Winter for Grey/High, Spring for Wood Elves, and Autumn for... something.