If you're planning on getting the best bang for your buck, I strongly suggest going with a custom build versus a pre-built machine. I've used tiger direct (in store, not online) to buy the parts for my computer, and if you don't feel comfortable with assembling it yourself, I believe for less than $100 they'll do it for you. Personally, if you have a retailer like tiger direct near by (relatively speaking) then you should definitely check them out. At the very least, you can go there for recommendations on what parts you'd need for your specific price point and desired specs.