In Darkshore there is a Cave with Worgens around 72,76.
You'll be killing:
Nightbane Tainted Ones Lvl 30-31 Nightbane Tainted One - NPC - World of Warcraft
Nightbane Vile Fang Lvl 29-30 Nightbane Vile Fang - NPC - World of Warcraft
For whatever reason, they respawn SUPER fast. Each mob drops about 1s, but are skinnable for Medium and Heavy Leather/hide. So each mob would be at least 2s a kill.