[halifax1]

If you have the official VGA cable then it comes with audio inputs. You need to buy a 3.5mm to Stereo plug, which plugs the white and red cables into your Mic In port on your PC.

There's like five threads asking this, you could have searched.

 

[halifax1]

http://www.monoprice.com/products/pr...seq=1&format=2

Only 65 cents.. works perfect for what you need.