Leather working is a good combo with skinning.
Depending on your class, you are effectively making armour for yourself, or sell it on the auctions to rogues, druids and hunters.
Also your gathering all your raw materials as you go anyway. I found that I was getting medium and heavy leather/pelts when I could'nt use them.
So I placed them in the bank and when I was of a sufficient skill level, I just withdrew them and levelled like crazy making items that incorporated the medium leather, because I had the stock available.
I have never been a crafter in any MMORPG, as it normally stops you being able to have a decent adventuring character, but playing a hunter with gathering skills, is infact really easy and just becomes routine to skin after kill.
All I then do is head to Iron Forge, sell my loot and deposit skins into the bank and then craft for a little while.
Repeat and rinse, hey presto rich dude!