If you really and i do stress really want to use a conrtoller, you can just use a 360 controller. It has a USB connector (the wired ones) that can plug in to your PC. It works with any steam games that say they are compatible. Most of the games are.
Note: many PC gamers, including myself, will gladly let you know that you will be at an aiming disadvantage with a controller. Console games include autoaim, and pc games do not. You get way more precision with a mouse, but that's just my recommendation. If you're into platformers, I'd recommend picking up a controller anyway.