I really need to get some sort of gamepad for my PC. I used to use a regular Xbox 360 pad with the Microsoft wireless receiver for PC but it died when my southbridge on my old motherboard was going bad; however, Microsoft basically aborted the thing and it is virtually impossible to find evidence that they even made it at some point, much less give you the ability to buy a new one.
Any suggestions?
yeah, I had a really hard time finding one! The only way was to actually buy a new X360 Wireless Controller for Windows that comes with the receiver (~$70).. Then I pawned off the controller to a friend with an X360.
Your best bet, in my opinion, will be with the Logitech F series, the ones that can switch between DirectInput and XInput.
The wireless choice:
F710The wired + rumble choice:
F510The vanilla wired choice:
F310Pros:
-Great d-pad
-Switch between DirectInput for legacy games or XInput for newer stuff.
-Quality material and firm, rubberized grips.
Cons:
-A little wide for my hands, triggers are far for my index fingers (that's more of a personal gripe).
If you'd rather stick with the X360 controller, the special edition controller with the transforming d-pad is pretty decent:

Pros:
-Much better d-pad than the original X360 pad.
-Solid build, with nice smooth texture.
-Analogue sticks have defined grooves that your thumbs grip better.
Cons:
-Requires the wireless receiver to work on PC.
-Discoloured face buttons: X is dark grey, B is grey, A is light grey, and Y is white instead of the classic colours I'm used to.
Alterntively, going with the X360 pd format, there's also the Razer Onza which is wired:

i haven't tried this one out myself, so I can't supply a reliable pros/cons list but it looks pretty sleek.