Well Warsong is rather obvious, just rock the Warsong set from the Garrison. As for Blackrock, what Firelands with ToT?! You'd look like a confused troll cosplaying Big Bird! The pvp version of t19, the red, black and grey one with the fire orb pauldrons are perfect for the Blackrock forge theme though, mixed with the either the pvp-skin Doomhammer or the Balance of Power Fist of Ra'den.