I've had "OK" results farming molten destroyers in molten core for blood of the mountain, it's needed to craft the hammer for sulfuras and can fetch anywhere from 750-1500 gold each.
Run in, clear them up to garr, run out, reset.
Best gold will always be playing the AH and learning how to do it properly.
As far as BC epic patterns I'd say just do old raids like hyjal/BT if you can, mob density is pretty high and I tend to get at least a blue BoE per week running on 1-2 characters.