If you are looking for a place with a ton of mobs I found a great spot in Sholazar Basin. There are skeletons that spawn right around this NPC http://www.wowhead.com/?npc=27801. They drop full loot and there is some sort of code that makes it so one has to be up all the time. I was able to farm here endlessly for cloth with my team. The only problem is finding time to loot all the mobs.