Your basic needs shouldn't be hard to come by, as well as most of the "nice" section. The only part that a basic laptop wouldn't be able to do is be an ultra gaming machine. You could play stuff like Neverwinter Nights probably and anything about that level. But, trying to play F.E.A.R. on that level of a laptop is a no-no

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eBay is cool, but I'm always a little gun shy of buying computers on eBay. If you can't find something you're comfortable with, just check local retailers or order directly from Dell, HP, Sony, etc.