sound card
Hey there...
I don't have any big revelations, but I have a fairly good system for recording, from the company Digidesign. Although it's likely out of your price range, here's a story that's relative: My friend bought a good mic preamp, a good mic, and began recording, one track at a time, through his computer's basic sound card. Interestingly, when he asked me to mix it for him, the sounds he produced were as good, if not better, than my higher end Protools system! The point? A good mic preamp, and a good mic might be as good a focus as what sound card you use. Of course, your basic computer sound card can only input one or two channels at a time, but if you're not going to record any live bands, with many mics, you might be able to get by with a basic sound card, as he did.
Of course, someone much more knowledgeable about analog to digital converters would probably say my story is full of holes, who knows!
Some other thoughts...
For somewhere around $300.00 Digidesign has a breakout box called MBox, which is ok. It mainly works with their Protools software, which is pretty sophisticated. This is the software that almost all major studios have used for the past 15 years, or so, and that most of the songs you hear on the radio have been recorded with. It is certainly a complicated piece of software, but very intuitive, and also a breeze to use, once you get used to it.
I think Roland also has a simple audio interface (another name for sound card/mic input box).
A company called MOTU has some basic recording systems. I think Digidesign just bought them up.
Musiciansfriend.com would be a good resource to find recording interfaces.
Anyway, good luck. I'll watch to see if you update your choices
All the best in your search.