Activision and RedOctane's "Guitar Hero" for the PC is a direct Xbox 360 version of the game and comes with a X-plorer model of the Xbox 360 controller. However, the game can be played on your PC with the use of a PS3 "Guitar Hero World" controller. The process of configuring your computer to use the PS3 controller with "Guitar Hero" is a fairly straightforward one.
Download the "JoyToKey" version 3.79 application and the "PS3 Guitar" config file (see Resources) to your PC.
Unzip the "JoyToKey" file with your computer's extractor application, and drag and drop the "PS3 Guitar" config file into the extracted "JoyToKey" folder.
Connect the PS3 guitar controller to your PC via a USB port.
Click on the "JoyToKey" launch icon inside the extracted "JoyToKey" folder to run the application.
Scroll through the controller list menu in the main application window, and select "PS3 Guitar."