I got mine on Amazon. Believe it or not, it worked first try and it turned out to be a Microsoft one. Drivers were not an issue once I figured out that some of my USB ports were powered and others were not - it needs a lot of power to work.
To get it working, you need to install the Microsoft Wireless XBox 360 Controller drivers manually, then go to the hardware manager and manually specify the official Microsoft driver as the driver for this device. Easy enough if you know your way around driver updates, but not plug-and-play. It works great, though.
