What you need:
-A Microsoft xbox 360 wired controller (don't pay extra for the "PC" compatible version. All you're doing is paying extra for the drivers disk, which you can get for free. As long as the controller is wired it will work on your PC).
-The Xbox 360 headset
1) Get the drivers for the controller at http://www.microsoft.com/hardware/gaming/download.mspx
2) Download the drivers and run the .exe to install the drivers
3) Plug in your headset to your controller.
4) Plug in your controller into your PC's usb port.
5) Click Start > Settings > Control Panel > Sounds, Speech and Audio Devices > Sounds and Audio Devices > Audio (Tab). Under Playback, choose your sound card in your PC. Under Recording, choose XBOX 360 for Windows (Headset). Click Volume for Recording and slide it to maximum.
If the headset connects to your Xbox controller this method should work, if not.. well this wont work. Hope it does