What mtb gear should I buy for a whole new drive train?

Being on short time, I guess that means you need to be able to upgrade quickly, I'd go to a href="http://www.pricepoint.com/" rel="nofollow"http://www.pricepoint.com//a for parts. I'd go with XT 9 speed parts to stay in budget and as you have rapid fire shifters now staying with a Shimano drive train will more easily allow you to do it in a few steps instead of an all night change over.