If you're really having problems levelling up at lvl 7, then perhaps WoW isn't really your game.
At 7 simply quest around in the starting zone, as a Troll that's Durotar (start in Valley of Trials and then move on towards Sen'Jin village and Razor Hill). In there you should be able to reach lvl 12.
Once at level 12 there are ample levelling guides (free and not-free) around on the internet to get you to 70 (or 60 if you don't have TBC).
www.wow-pro.com has some decent guides (especially Jame's levelling guides) but the most people will talk about Joana's Horde levelling guide.
Hope this helps a bit
