PC audio with S/pdif input only

Ok, I am really in the dark when it comes to computer audio....

What I want to do is have the ability to run Itunes, pandora, internet radio etc. through my Simaudio Andromeda. The Andromeda only has the S/PDIF digital input. My goal is to run a digital signal only into this connection and let the DAC's inside the player do the thinking. Not too difficult I don't think but I just don't know where to start.

It sure would be nice to do this wireless....... don't know if that is an option.

I have an imac with the airport extreme running wifi throughout the house but I was thinking of getting a laptop to do the computer audio in my listening room. From what I understand I could get an airport express and plug into this room extending the wireless.

Other option is just a short cable from a laptop but most new laptops seem to be usb?? Do they make a converter for usb to S/PDIF.

Is the S/PDIF connection capable of extracting the bit rates to make it worth my while i.e. close to cd quality??

Thanks.