http://www.worldofwarcraft.com/info/

for leveling guides…

wow-pro.com

and last but not least, my most prefered method of leveling..

The FASTEST way to level up is quests, download the following addon, it'll make your questing way easier.

http://www.wowinterface.com/downloads/info7017-LightHeaded.html

and

http://www.wowinterface.com/downloads/info7032-TomTom.html

Basically, when you open up your quest log, instead of having to tap out to find quests (I personally hate reading the quest logs, I read what i need to kill to get ..you know how its usually kill so many of so and so..so I would tab out and look up their location) you'll see the lightheaded addon attached to your quest log, it'll have detail info of what you need to kill and where it is, and the beauty of it..is..it'll have coords!

Just click on the coords (and this is where tomtom addon comes in) and tomtom will place the coordinate on ur map, so when you press M, you'll see all the locations.
References :

http://www.wowwiki.com
References :