So ya wanna be an RPer, huh? Well, pull up a chair and share a drink and your tales with us, then!
...What's that? People don't seem to like your Human Priest's chosen name, Johnny Awesometon Stormrage? That's a shame. This thread is intended to help you choose a racially applicable name for your character. Let's start out with
Orcs are some of the easiest characters to name, in that the convention is so simple. Most orcs are given their first name by their parents at birth, then move on to earn their last name. Someone who has great affinity and friendship with wolves may become Drakor Wolfwalker, where someone who has worked much with the elements may become Mrok Flamequake. Generally, treat the first name as the name and the second as a title. This doesn't mean that Drak Handofadal or Grosh Championofthefrozenwastes are good names, though - Stick to [noun][verb] or [noun][noun] as far as possible.
As for the first name, lots of Rs, hard breaks and Shs are good. You can write a good orcish name outside of these, but it's likely to sound out of place. Generally, stick to one, two, three at most syllables. Good examples are Garrosh, Krom, Varok and Reghar.
Trolls are a bit more complicated. Their names are typically meaningful syllables put together to describe them (see http://wowwiki.com/zandali). Trolls do not generally take last names, so that is very much discouraged. Generally, troll names are tribal and primal-sounding. One way of making a good troll name is to use the [syllable]'[syllable] convention (Sen'jin, Vol'jin, Zul'jin). You can also make non-apostroph'd names (Samambah, Zalazane, Rokhan). Generally, try to get a name that rolls off easily.(Avoid the 'jin suffix, as well as the zul' prefix, as these are mostly reserved for leaders and great spiritualists. If you DO take these, explain why in your bio.)
Ah, the tauren. Lovely people, except they don't know how to make a good burger. Their naming convention is similar to humans, with [first name] [clan/family name] being the standard denominator. It has ocurred that Tauren have taken a name themselves after a great achievement to commemorate the act, so this is acceptable too. Male Tauren first names are vastly similar to orcs' in many cases. Exceptions include the ones with drawn-out wovels (Baine, Cairne). Female names are softer and calmer-sounding (Nagara, Bessa, Eruna). As for clan names, it is generally inadvisable to invent your own clan. Follow this instead.
When I say Forsaken, I mean reanimated humans primarily. You CAN RP a raised orc or elf (I personally RP an undead Blood Elf), but in these cases it is recommended that you follow naming rules for those races instead. Forsaken names in themselves are, just like those of humans, split into [First name][Family]. Generally, Forsaken sharing family names are uncommon (there have been cases, such as the Agamand family, though these were technically scourge). When naming your forsaken, 17th and 18th century British names are a very good denominator (Ronald, William or Jonathan are great contestants). If a Forsaken cannot remember their name, they may make up a suitable name or simply take one from a headstone. Some invent surnames that imply their desire to eradicate the Scourge. (Thank you for the blue, Drawz)As for family names, almost anything goes(generally, abstract ones work the best though)! Be creative.
Elven (Quel'dorei, Sin'dorei, and everything inbetween)
Elves typically take very rolling names. It goes [name][family name] like humans and Forsaken, but in the case of elves, the family name is often descriptive ( [noun][noun], Starwhisper, Manasong, Sunspire ). For male elves, the first name is rolling smoothly (Lantharion, Velathion, Fereldin - in fact, -ion and -din as suffices work at lot of the time). For female elves, they are softer and calmer like those of the Tauren females (good examples are Thessalia, Thalinde, Salissa). -inde and -alia are good suffices here.
Ah, gnomes. Loved by many, hated by more. Gnomes are born without a last name, which, like in the case of the orcs, is more of a title that the gnomeling (did I just say gnomeling? o,O) has to earn for themselves. Gnomish first names are abstract - be creative! The title should be related to your character's backstory. Did he once crash a flying machine? Why, Zatfronk Crashbolt it is! Did he ever set off an explosive charge with his hammer, detonating a mine of troggs? Hello there, Gezzix Nitrohammer. (I once RP'd a gnome warlock called Jingo Lolbolt. See where I'm going? :P) This convention works for both gnomish males and females.
A human? What's that? Some kind of... Oh, right. This should be straightforward. It's the only race that allows you to use your real name, but if you don't want to abuse that, fair enough - there are loads of choices. One of the most straightforward and least complicated races to name. Do note, though, that if you take a foreign-sounding name, you need to have a foreign character. Yang from the southeast reaches of the Eastern Kingdoms is alright. Abdul, who is white and has lived in Stormwind all his life, is not.
Beer, beer, beeeeer- What? Oh, right. Dwarves. Dwarves very typically have scandinavian-sounding first names and descriptive last names, like elves and tauren. Good examples are Magni, Borin, Bjorn or Rothgar. Last names are typically family names, so you're free to be creative
Coming up: Draenei, Ethereals, Demons and other nice things from the nether
Since Thara's been away from here for a long time, he's probably not going to finish this guide. If theres a race you want to make a character of, and it's not here, check it's respective page on wowpedia.com for a general idea of what names should be for that race.