Look at the Presonus firestudio Tube. It has the 8 Mic plus 16 more analog that could be used for mic/guitar/watever only $200 more prob good deal all hooked up with firewire. Also on the computer it does not have to be all that powerful but I would go qaud prob 4 to 6 gigs ram some fast hard drives to be able to track all 12 incoming inputs... SSD if you can afford.
Oh, I overlooked the analog inputs on the tube! Thanks so much for the info, I will run it by my friend.