Is this the last hurrah for anyone's computer?

[Lemur]

I'll second ibuypower as a good source. They sell high-end gear for scary cheap. I priced out my gaming ideal at NewEgg and then at ibuypower, and it came out 10% cheaper from the builder than if I did it myself. Also, they allow you to buy without an OS, so if you have a legitimate copy of Windows you aren't forced to buy another, which is very polite of them. Most builders will not sell you a PC without an OS.

The main downside of ibuypower is that they sell a lot of hideous cases. If you're very, very lucky you can find something that doesn't have dragon eyes or leopard stripes or giant twirling glow-sticks for fans.

-edit-

And I hate to sound like a broken record, but don't restrict yourself to only thinking about Nvidia. ATI has the best stuff in a price/performance sense right now. Also, their cards run cooler and draw less power, always a good thing. The world of graphics is constantly changing, so it's not helpful to ignore either of the big two makers; you gotta keep up and see who's got the best bang for the buck. It changes from quarter to quarter.