OK so how do I plug a AES/EBU cable with a 24-bit 96Hz digital signal from a A/D converter type Device (Finalizer) into my Powerbook?

I want something small and compact so I recently bought this:

http://www.roland.com/products/en/UA-1EX/

But the more I'm learning about digital cabling, I've realised the damn thing has Tos-link digital inputs so that's been a complete waste of cash arrrghhhh!!!

Any ideas? Or am I gonna have to go for a higher-end sound card with AES/EBU inputs do you think?