How can I control a remote controlled car with a computer?

I have Microsoft Robotics Developer Studio 2008 R3, a Bluetooth adapter, an Xbox 360 controller for Windows, and plenty of RC cars. Where do I go from there? Or is there another, free, program that does what I want it to?
Or perhaps is there a better method?
I want an easy method of doing this, please.

This is no simple one step process, you have to do a lot of work and research to get something done like that. Google will be your friend for that research.