I'm really new myself, but a couple of things I've learned...
* Loot them corpses. If it isn't a quest item, you can sell it. Discover and remember the approximate values of things in the area you're in, so if you have to make the choice between two different items, you'll make the right (read: profitable) choice.
* Groups are your friend. Find people to grind (or whatever it's called, with the grouping and the killing and the questing, flaigen) with, they will save your ass.
* Read the stuff on the interweb about good class/race pairings. I started out as a human warrior, rather standard, but pick somthing that'll suit your style.
* Have fun. People turn WoW into Serious Business?. It's a freaking game, man. Enjoy yourself, go at your own pace. And ignore the idiots that laugh at you mid-battle. (This happened to me a couple of minutes ago. Christ, I'm only level 8, go pick on someone your own size, assgoblin.)