No cloning allowed
But first, a word of caution: a character named, "Lleggolas," "Sefirothh," or "Hermyonie," is the first step in the wrong direction. The two character ideas I gave above already involve enough "mixing" that the "matching" shouldn't be painfully obvious or annoying. If one were called "Sherlocsparo," or the other "Frankensteen," however, it would most certainly irritate other players, like thorns poking in the eyes of everyone who sees them in the game -- avoid direct copies of other characters names like you would the Ebola virus.
Also note that you should at least have two or three different inspirations for your character, not just one. Even if you're character is called "Azragoz" or something, he'll seem bland if he can only repeat what you've heard the Terminator say all the time. If you choose a broad character archetype like one of the ideas below, be sure to add something of your own to mark it as yours, kind of like the undead based on Frankenstein's monster -- who also finds that the sight of a doll helps appease his anger, frustration, loneliness, and bloodthirstiness (or alternately drives him further into it). Add some interesting quirk to help add your own spice and distinctiveness to your character.
Below are just a few extremely broad characterizations to help get your creative juices pumping. (Also note: many of the links in this article lead to collections of quotes from interesting characters that can inspire you when looking for something characteristic to say.)
The "stupid guy" is certainly one of the most naturally humorous characters you can find in any story, and he also adds a certain endearing quality to your character as long as you don't take the "stupid" thing to extremes. In fact, Leeroy Jenkins, undoubtedly the most famous RP character in WoW, is a variation on the "stupid guy" theme which has proven extremely successful in the hearts and minds of WoW players everywhere.
Possible quirks: Like Forrest Gump, Fezzik, and countless others, you may want your character to be innocent, likable and extremely talented in some other way to make up for his deficiency in intelligence. Perhaps he or she is extremely good at posing puzzling yet oddly perceptive questions, like zen koans. Or, you may prefer the wicked sort of dumb guy, like the bruiser in most fictional bars around the world, who also happens to have a soft spot for bunny rabbits, frogs, and other innocent little critters.
Warning: Resist the temptation to make a character named "Leerrooy," or run around shouting that name. That joke is old now. Vary the theme to try and find something different, yet equally funny.
The "brave adventurer" type has a lot going for it, especially motivation. All characters need something to drive them forward, and in many cases, this will be the pursuit of interesting and magical items. Given the prevalence of magical items in WoW, this character should mainly be interested in difficult-to-get items with some sort of backstory involved in them. Even if you don't know of any background story for the Whirlwind Axe, for instance, make up something on your own based on the relevant in-game text and reward other players who help you get it with the reason you are interested.
Possible quirks: Indiana Jones, Lara Croft, and others tend to have some sort of stable day job which keeps them busy most of the time they are not out on adventures, and this also provides a reason why go looking for the objects of their desire. Your character could go a different way by being a former shoe-shiner, for example, whose main wish in life is to collect the very best boots in existence; or a new-agey fortune teller who loves to collect the most mystical gems and crystal balls; or even a mad hatter -- need I say more?
Alice in Wonderland
The "young explorer" is always youthful, sometimes barely more than a child, and brings with her all of the inquisitive nature of childhood. Asking questions drives these characters, as they seek to know everything they can about everywhere they go, and everyone they meet. This is handy for a roleplayer who doesn't know much about lore, but enjoys learning more. It's also very good for a sociable person who likes communicating with other people as much as fighting alongside them.
Possible quirks: Like Alice and Dorothy, it's good to be relatively normal and curious. In the case of an "everyman," like Arthur Dent, a character can even be especially normal -- unexceptional in the extreme -- and his or her explorations are accidental rather than intentional. These sorts of characters tend to be clumsy, possibly embarrassing themselves a lot, yet more often than not they are extremely lucky when it comes to staying alive and beating the bad guys in the end.
"Normal" quirks go a long way with these characters, helping to clarify the contrast between them and the crazy world they live in. Perhaps they rely on a coffee addiction to relieve adventuring stress, or have a tendency to say "Oh my stars!" whenever they get surprised. Perhaps they are just perpetually in search of a really good bath.
A list of character inspirations can never be complete. Experienced roleplayers often have a long list of their own inspirations for each character they've created -- so many, in fact, that the resulting products seem little like any one of their story ancestors. Sometimes an inspiration can be an idea as simple as "flighty butterfly" or "quiet smile," without any reference to popular stories whatsoever.
What sort of inspirations strike you as most interesting? What character archetype would you add to my list?