I have a Creative Inspire 5.1 5200 speaker system for my PC.
http://images.creative.com/iss/images/products/headers/prod55_hdr_1_6_1.jpg

Is there any way at all to hook this up to my T.V./Xbox 360 and use it as the sound source?

Use cable splitters to hook up your sound to anything you need, I got my stereo system hooked up to my PC, TV, DVD, and Wii.

wow!
hire someone!!
that is friggen sweet

Dont hire someone, that would be a waste of money. But my sound has the cord you plug into the back of the PC, theres also a slot on the back of my LCD tv that fits perfectly and is for the same use.

Tianam, is your TV LCD or Plasma?

LCD can properly utilize computer speakers. Plasma's need to have a matching version of DirectX sound.

go to an eletronic stor and find a splitter what tv you have?
if its a plasma or lcd it shouldnt be a problem

I didnt even know Plasma's could do that.