What I found most useful for my leatherworker is making an alt with disenchant.
You're probably still going to lose money compared to just selling the skins, but at least you have a use for all the items you craft. When leveling LW, target green items. Then ship them off to your alt to disenchant into mats.
I spent a lot of time farming raptors because besides the leather, you get raptor hide (basically farming two mats with one fight) The raptor hide harnesses disenchant into mats that will sell nicely on AH.
Once my level exceeded that, I went on to the turtles in gadgetzan, which as far as I'm concerned are the best source I've found yet in the game. You get turtle meat and clam meat for cooking, pearls, nice green drops, and then skinning gets you leather and turtle scale.
the power leveling guides for LW won't get you as many greens, but if you put more effort into making green items, at least you aren't crafting a bunch of junk that has no value.