In Mount Hyjal The Best place to farm Savage leather is at Sethria Roost . The Mobs are Twlight dragonkin and have a very fast spawn and not too much health .The spots also drops blackened dragon scales and a greater percentage of leather Scraps so if you lower level this is a great spot to farm .
The Obsidiam forest
This is the Best spot for range dps to farm Savage leather , sit yourself on top of a tree and dps the dragons flying about. If your not a ranged dps the mobs are all about on the gound you can tag them and then drag into the NPCs to help with the killing.
The other Great spot for Farming Savage leather in Twilight highlands is from the Black Breach down towards Dragonmaw Port . You will find Different mobs such as Owls,wolves,gryphons and elks ,all of the mobs can be skinned and have a great re spawn rate so you wont have to wait long for the re spawns.