Anyone know where to find an audio cable converter?

Im looking for a converter that would be female to female. One end being those stereo red and white connectors and the other side the small headphone type connection. So that I could say connect an xbox audio cables to it the plug in headphones to the other end.

I really don't know why im having such trouble finding anything like this, if you know why no one seems to have this that would be nice to know. Reason being i want to hook my xbox up to my computer speakers. If you can think of any way for me to make this work it would help a ton.

I know the cable you are looking for and they are VERY hard to find. This is the closest thing I can find:

http://www.cablestogo.com/product.asp?cat_id=2009&sku=40424&iorb=4764&cm_mmc_o=PwYBEp%20qRGCjCQmmVCjCW-CjC-kk

With two of these adapters, I think you would be good to go:

http://www.radioshack.com/product/index.jsp?productId=2102665