Hi, I am 21, and I would like to start recording music from my keyboard, mic, and guitars via computer. I want to purchase Acoustica Mixcraft, which I've heard is the Windows equivalent of GarageBand. However, I'm unsure of what hardware I should use to mix in the instruments. I don't mind doing them one at a time, but I have nothing to plug the instrument into my computer with. Do I need a special audio card, and what kind of cable do I use to connect a keyboard / guitars?

Any help would be greatly appreciated.