I love it when the fun stuff happens. My main is a frost mage, and I rolled a warrior after I kept getting crappy tanks in instances (I've learned soooo much now that I have a tank myself).
I've been leveling Protection (yes, I'm crazy, but 1 hand spec FTW), and the best advice I can give that isn't repeating someone else is to be sure to use your stuns. I was in the badlands a few weeks ago, and a 45 blood elf mage starts winding up a pyro (pvp server), so I charge, Hamstring, he blinks, Intercept, Whirlwind, he Frost novas, I hit Concussion Blow, all the while just smacking him around. This sort of thing continues for a while as I kill him through his mana shield. The trick to it, is to keep the mage from using his tricks to kite you.
The next week, I saw the same mage try it again, but this time he was frost spec. I got hit with frost bite on his first frostbolt, and he was able to just keep it up. The one time I actually got close (intercept + Concussion Blow), he was able to shield, frost nova and blink away. After this happened 3 times, I got my wife on (balance druid), waited for the mage to show up again, and proceeded to rape him with all the stuns and snares a druid and a warrior can do.
Moral of the story, perfect counters, or a healer is the only way to win.
From a mages perspective, warriors are almost free kills. Every three minutes, for 45 seconds, I can kill just about any class up to 4 levels above me (does not count level 70 or BM Hunters). This can start as early as level 50 with a mage.
Icey Veins +
Summon Water Elemental of Doom + Frostbite + Shatter + Coldsnap means that a mage has 4 frost novas, each of which give him an additional 50% crit, at 200% damage.
Right now my mage is level 66, and even without blowing my Coldsnap (rarely necessary) I can put out 8000 damage in 8 seconds. (Frost Nova ->
Frostbolt+
Ice Lance ->
Freeze (Water Elementals frost nova) -> Frostbolt+Icelance)
Armory links:
Mage and
Warrior P.S. Don't get Icey on your sword, I thought it would be useful for runners, I was wrong.