You're on the right track. Now you need a program to create your mix disc from your .wav files (six, right?) Don't forget 5.1 speakers for monitoring your mix. And also a program to create the 5.1 disc in Dolby Digital, DTS, or whatever.
I use Mark of the Unicorn's Digital Performer for recording, but only for stereo. DP4 can create a mix for 5.1 surround, but (as of now) can't master a disc in 5.1. Programs like Apple's Final Cut Pro should do the trick, and some third party companies make standalone software for Dolby Digital or even DVD-A disc creation from 5.1 mixes. This link is just one such company:
http://www.minnetonkaaudio.com/
WARNING: I've never used their products and I only know them from reading their website. Do not take the above as an endorsement from me.
You might be able to find cheaper options for all of the above, but since I already own DP4 I can use that when I'm ready so I don't know what else is out there. I'd be surprised if most mixing software doesn't create even a basic 5.1 mix by now actually.
Your needs may be better served poking around a mixing newgroup, as these forums are mostly for playback of pre-recorded content. Both are very music-orientated of course, but I'll bet the biggest difference is the average income is higher here (just a joke from one struggling musician to another!)
-Marty
