One of my favorite ways of farming on my old main (70 lock) was to use this spec:

http://www.worldofwarcraft.com/info/...00000000000000

I grabbed a bunch of "of stamina" greens from the AH. got my hp up to about 16K (these greens allow very low repair bills also) your spell damage is way way low, but you are regenerating 400+ hp every few seconds with voidwalker demonic sacrifice. Just run around using seed of corruption, as the low spell damage allows more to be collected before the explosion happens. The things explode, you loot, and keep moving.

Just another spec for thought.