Using PS2 controller on PC.

Hi, I was playing DiRT on PC and then I realized how much it sucked to play using keyboard so I was thinking, is there anyway to do that besides going to an online store and buying a $15 ps2-pc usb port? I just don't want to buy online and if it costs that much, I think I just should buy XboX' universal controller... which is kind of expensive. Any help would be appreciated. thanks.