You might want to get all the 339 pvp gear at the AH or at least replace your green items. The pieces are about 150-300g each. Also do the Crucible of Carnage or whatever to get the 333 sword. Twilight Highlands gives you at least 3x or 4x 333 blue items, and some really good +str trinkets. Also, make sure you go to all the rep vendors and get whatever upgrades you can. I think Hyjal has an item or two, and Therazne or whatever (in deemholm) has 2 rings you can use and sholder enchants you can use. Within an hour or two of hitting 85 after I enchanted my gear and bought some PvP gear off the AH, I was doing 9k DPS on target dummies.

Also go Frost or Unholy spec for DPS/PvP