That's pretty steep even for a pre-built. If you really want, I'll give you advice on parting out a better pre-built, but not before I pitch you on building yourself.
I agree with the above posters, a home-built rig is easy to put together. To extend manofchalk's comparison, the average computer is easier to assemble than the most basic Lego kit. Seriously. It involves screws and stuff, but there are fewer parts to put together and it's very apparent where everything goes.
You also stand to save quite a bit of money. If you're willing to put $1500 into a pre-built, you could either get a slightly better rig for $1000 or nearly twice the performance for the same $1500 building yourself.