Well, Dragonscale Leatherworking certainly comes in handy during the mail conversion at level 40, and later on, the Dragonscale sets will make you some money. But if this is your first character, get rid of Leatherworking, and get enchanting instead. You WILL need more money as a first character, than a second or third. While you quest, you skin and disenchant. Check the AH prices, and sell the stuff. This will help you alot.
A couple of other tips for a new guy:
1. GET MORE BAGS! They are expensive, and I have rarely seen them drop much in the first 40 levels. Try to find a tailor who can make you some bags if you gather the cloth needed. Cloth drops from Humanoids by the way. If you get the materials, most crafters will not charge much or anything at all for the bag/item until you hit 40+. Bags WILL make your life so much easier, since you will not have to either run back and forth from your questing area to a vendor all the time.
2. Don't throw ANYTHING away, unless absolutely necessary. Pick up all the useless stuff from the mobs you kill. Tuft of Hair? Not worth a damn, but after killing things for two hours for quests, you should have enough of them to get quite a lot of money from it. Almost anything in Gray is vendor trash, but that doesn't mean you can't profit from picking them up.
3. When you group with someone your level, and find that they are nice people, add them to your friends list. This may come in handy later on. When you decide to do an instance, but lack that Warrior/Priest/whatever, you can check your friends list. Might be someone you have grouped with before that could fill the missing spot in your party.
4. Read forums like this. There is alot of useless thrash threads even here on Allakhazam, but you will find tons of information worth sifting through. The sticky up on the top of the Hunter Forums, will give you more than enough information for your first 40 levels. Hell, I sometimes come back and read it again, and I am 52.
Ok, I suddenly realize I have been ranting on in the Trade Skill forum... Now why would I believe I was in the Hunter forum?
Anyway, hope this helps
AI