A serious AoE'er who wants your aggro is going to get it. If you know who it is ahead of time, the easiest thing to do is slap vigilance on them, and when they start getting hit, you'll get free taunts to get your mobs back. If they die, well, maybe they'll learn from the experience? (Probably not, I know a lot who haven't. heh I don't have much pity for folks who treat warriors like paladins in AE situations and expect to never pull.) Otherwise, you're pretty much stuck with TClap, Shockwave, and tabbing through with devastate and HS or Cleave.
Your best bet for getting mob health where you can keep an eye on it is going to be turning on nameplates. If the default ones don't suit your fancy, there's an addon called Aloft that you can use to customize them quite a bit. Other than that, my best advice for what to do for good warrior addons would be to go look at the list of them that folks like Lore and Cider are using in the UI/Interface forum.