I'm lookinf for a Joypad

360 controller works great

You'll want to use the X-Box controller on the PC (you don't need an adapter, you can just plug it in -- it's USB.) Not just because it's a decent controller (although it is), but because it's the industry standard now and most games are designed for it anyway, so you generally won't have to configure it or fiddle with external software to get it working the way you would with anything else.

360 controller. No ETA on steam controllers as far as I know, and you don't really know how they will turn out. All games out there that supports controllers show xbox controls anyway.