sogone,
If you're the kind of person that likes to learn new things, then assembling and building your own PC will save you some cash - and its not that hard at all.
There's tons of resources on the web - you can build a machine that will compare to anything from Alienware for much, much less if you do it yourself.
I don't think you should get a pc for any type of gaming if your wanting to save money. If you really want to play games get a console system like PS3 or Wii. If you want a pc just for surfing the web and your school work, get a nice ThinkPad from IBM/Lenovo. They have the best laptops, but thats just my opinion and I think since your in College a laptop would be best for you. This might be more expensive right off, but in the long run I believe it is a better idea. The best video cards these days will cost more than $500 each, and if you really want good performance equal to a console machine you will need two!. Plus the cost of everything elese. So if you want to play games wait till you can get your hands on a PS3 or Wii, those will last are more popular these days for gaming than pcs. XBox360 is also a good choice. Yes this might be more expensive at first, but in the long run a "gaming pc" will be obsolete far faster than a new console. You can get a nice laptop that will last you through college and you'll have the cosole that you won't have to replace till the next generation of consoles comes out....This just makes the most sense to me in a financial standpoint...
T-Bone has a point here, if you wanna play games and save money, consoles have got to the point where they are a great choice. Ive played a PS3 and Xbox360, and while they're fantastic machines and well worth the price - the PC I recently built smokes them in terms of graphical detail, sound quality, etc. Of course it cost a good $2k too - T-bone's idea of an inexpensive laptop and a PS3 or XBox360 for your gaming is much more practical.
However, if you want to play a game like Battlefield and arent worried about maxing out every little detail setting - you can definitely build a gaming PC for under $1000 that will perform great.
If you're going to go with a single core chip, the AMD 64 line is an excellent value, and a ~$150 - $200 video card will be more than capable of playing Battlefield without a problem.
I'm sure you build an entire system, with Widescreen LCD monitor and everything, for ~$800.
BV