If you have an spdif output on your soundcard, you could use that as well. Your stereo system has to have an spdif input though.
Here is an adapter like the one that I am using. It has male connectors on the rca side, but you can get female ones I think. If you get one like that you just have to get a couple barrel connectors to connect the rca cables up, no big deal. This one was actually given to me so I decided to just use what I had.