Need Help Getting 5.1 Surround Sound from iMac

[gerfuls]

I have an aluminum iMac and I want to set it up with my Logitech 5.1 Surround System. I've heard about some kind of adapter you can get that uses optical sound (TOSlink) from you 1/8" jack but I can't seem to find where to find it. Where can i get such an adapter or is there another way?

 

[DJ567]

http://www.google.co.uk/products/ca...&cid=12430813472282084817&sa=title#ps-sellers
you need something like that, i have 1 it works very well but its very short so i usually just use line out to phono cable

 

[Capt Crunch]

You need this:

http://www.monoprice.com/products/p...=10423&cs_id=1042301&p_id=2671&seq=1&format=2

Get every cable and adapter from monoprice.com. If you're feeling generous, you can paypal me the savings.