Mystic Forge
You’d be better off using the mystic forge in the mists. The reason for this is because it’s easier to get the other things you’ll need in the mists, rather than in LA. There’s a vendor there who allows you to buy things like a PvP salvage kit for glory (which you’ll need). As you play PvP, you’ll get reward chests, which will include skins. Some will be doubles. Salvage the ones you don’t want and use the stuff you get from the salvage to make the item.
This is what it says in the wiki about it:
PvP items
When PvP rewards are salvaged using a PvP Salvage Kit, they are turned into PvP crafting materials, such as arcane powders, arcane crystals and tokens. The tokens all have different ranks (i.e. rabbit, deer, tournament, etc.) and generally the higher the token’s rank, the more imposing the item forged.
To create an item you need an item token (available from a glory vendor), a rank token (Rabbit, Deer, etc.), an arcane token (crystal, orb, sliver, etc.) and some arcane powders. The combination of rank token and arcane token determines the rarity of the item.
Hope this helps.
I think PvP armor can only be used in the Forge in the PvP Lobby. It’s by the gear merchants.