Pokeprof asked..."I've got a question. Where exactly should we start off about learning more about the lore of WoW? I mean, I know playing the Warcraft games help, but don't supply everything, like how the Defias Brotherhood came about and what not. So where can you get the background on everything you need to know behind the lore?"
I can't recall any orange-glowing Undead in Northrend beyond Zul'Drak where it's explained to you in a very detailed questline. If you haven't done it, I highly recommend it. Just head over to the Ebon Blade camp in Zul'Drak and it'll get you started. If there are orange Scourge elsewhere in Northrend, please leave a comment on this post informing me of where, because I can't think of any!
"I only roll trolls if I can help it. Why don't they take out Zazalane and expand Sen'jin village? Trolls have like the worst "home" in the game, just a collection of a couple huts. Or even to take back Stranglethorn Vale."
People hate the 'static worlds in an MMO' answer, but so far that's probably been the reason. The Trolls could get rid of Zalazane, but it'd remove a bunch of awesome quests for lowbies.
However, I bet this or something like this will be happening in the next expansion. Now that they've been able to work in phasing more heavily than they did in the Burning Crusade, I can definitely see them using it not only in quests, but to actually evolve the world. They could add new content on top of the old content, and not really hurt anybody. They could probably do this with Gnomeregan as well, but if they do I really hope there's a questline that actually covers how they get rid of the radiation.
I fully expect to see the Darkspear Trolls in a big role in the next expansion. It's just a feeling I get.
"Why do the gnomes not have a healer class?
They were discovered by the dwarfs and before that apparently lived isolated, yet they have no healers. Were there never a need to build a robot surgeon? Invent stimpacks? Induced coma-helmets?"
Gnomes have definitely had medics, but they don't have Healers in the way the other races have Healers. The Gnomes generally don't put much stock in higher powers or anything like that. They don't reject their existence, but they're not interested in that sort of thing. The healer classes, unfortunately, are all those sorts of people. Faith in the Light, or in touch with the Spirits or things like that. That's not really a Gnomish kind of thing.
Were there a Gnomish healer class, it would be something that no other race would really do. Gnomes would be very scientific in their approach, using things like this Bonechopper to 'fix' things. That's uniquely Gnomish, and they try to make the classes things that multiple races would have. Gnomish Medics will have to stay in your Pen and Paper games, because you probably won't see them in WoW.
Though I admit, it would be fun to amputate my raiders' limbs to cure what ails them.
"What they don't tell you about the Gnomeregan disaster is that in addition to heavy levels of radiation the city was also blighted by a terrible sound. A hinky kind of puppet show tune that just goes on and on and on....
Anyone trying to re-inhabit now would be driven mad within just a day or so!
Sure they can clean up the radiation but there's no way to get rid of that darned tune!"
is a very good resource if you want to look up specific topics. Here at WoW Insider we also had (and will have again) a series called Know Your Lore
that has covered certain topics. You won't find everything you're looking for there, but it's still pretty good! Wowwiki has just about everything you want. Just be mindful that it's a wiki. Sometimes you'll want to double check things with the sources they provide.
Ask a Lore Nerd is here to answer all of your questions about the lore and story of the Warcraft universe. From the religions of the universe to the 'evils' of Azeroth, everything is fair game. If you want more in-depth answers to some of your questions, you may find what you're looking for in Know Your Lore.