It's an old guide but it still works! It shows you the best places to aoe lvl (which for some is alot more fun then questing).
It shows what you should specc.
It starts @ lvl 28 (possible at lvl 22 but harder)
I've done this myself on my mage, and it's alot of fun.
The_Art_of_Grinding.wmv - FileFront.com
(Trying to contribute) <3