A couple of other things to keep in mind:
Try to find out the battery life of the laptop you're looking at. If you plan to keep it plugged in most of the time, and just want a laptop so you can play in front of the TV or something, battery life doesn't matter much. But if you intend to take it on the airplane, etc or other place where you don't have an outlet, battery life is very important. It should also be noted that thing like games drains battery a lot faster than surfing the web or word processing. And the "made-for-gaming" laptops (like Alienware) tend to have the worst battery life of just about anything you can buy, because many of them are pretty much desktops crammed into a laptop case.
Also, once you buy it, do not look at any other sites, computer stores, etc (this goes for most computer buying, really). If you buy it online, by the time it arrives at your door, the same model computer will probably be at least $100 cheaper, and a new, better model will be available. As soon as you click "Buy" do not go near anything selling computers. It will just depress you.
Good luck on your computer hunt.