Just about any card will work with Cool Edit.

So how does the whole sound card thing work. I install the PCI card and hook up the box to it. Then on the computer, is there software that comes with it? Or how does it interact with Cool Edit or some other multitrack recording program?

The program will detect the card after installation. There is usually a little software control panel provided by the soundcard manufacturer that can function as a basic mixer and a means of setting things like buffer size and sample rate, but mostly, you will be controlling that with your software. It's really not that hard.

Awesome thanks