Hi, I'm also looking to buy a new gaming rig. You didn't mention if you wanted a desktop or a laptop. I'm looking for a laptop because I need it for work, so I kinda require mobility. So far I'm eyeing Horize, they have some neat machines and they give you suggestions too. There's also Alienware, smooth looking laptops but they seem a bit overpriced. I'd say you need a minimum i7 processor, 4GB RAM and a HDD 7200 rpm.
As I said in my previous post, I was also looking for a gaming laptop. It took a while to decide, but I went for this: Horize. I'm extremely happy with it, it runs perfectly, when it comes to both editing/rendering and gaming. Yesterday I played BF3 with maxed out settings, had no problems woth overheating, it was a thing of beauty! If you're still looking for a laptop, I'd definitely recommend Horize, you can customize your laptop to fit your budget, I mean for $1500 you can definitely get a sweet rig.
great website that will help you build a pc from scratch, read the feedback on products
List of what you need for your epic computer:
Harddrive or SSD drive or both
media drive? this would be your cd/dvd drive or even bluray nowadays