Alright Tards. Listen to the level 40 who made 200g in two days, bought an Epic bow, and a mount, an' still had money for all the fancy mail stuff and then more!
Just go on AH - Buy blue items that are selling for low-low, Sell them for around 20g. These are my settings..
Any blue item from 30-40 - 15-20g
Any blue item from 10-20 - 3g-6g
Any blue item from 20-30 - 3-9g
Aaannnd.. Any epics over level 30, 90g+
Make sure you save up enough for Mithril Spurrs, and stuff.