You have so many options available to you. It will make you crazy. To go strictly the computer route, the PreSonus Fire Box/Studio is a very nice sounding and popular FireWire enabled unit. It comes with some lovely software that I personally have found a bit confusing. But I'm old and I don't adapt as quickly as I used to. So the software that I run is Adobe Audition & Sony Vegas which are my personal choices. I have entry level Pro Tools which really doesn't turn me on much.
All you need is a tag of Shure SM 57's and some foam pop filters. So that's $500 for the interface and $800 for the microphones. One pair of Sennheiser 280 headphones and 4 Sennheiser 202 headphones and you'll be cooking with gas. You'll also need a simple headphone amplifier for one other musicians need to be overdubbing parts. You'll also need a pair of control room reference monitors. Inexpensive KRK's are some of my favorites. And that's really all you need other than some microphone cables and stands. The whole package a little under $1500.
If somebody tells you the 57's aren't the best mics to get, they don't know what they're talking about. So beware.
Mx. Remy Ann David