If you put a deposit down on the tour you like before Dec 15th 2006 then they will take 10% off the price.
STA like most of the travel guys recently announced their early bird flights. So you may even be able to get yourself a cheap flight
No cashback with STA - but there is cashback with Webjet
Also STA are running a competition to win tickets to the Make poverty History Gig - you just need to subscribe to the Mile High mag.