1) What's your mic budget? $5, $50, $100? Total budget?
2) Unless you need a 4-track for portability, you'd be better off in the short and long run to record with your computer. If you use your current sound card initially you can get a mic such as the Studio Projects B1 for $80, a pre like the Audio Buddy for $80, software for free for demo versions, or N-Track for $40. So for about $200 you're in business. You can upgrade to a better soundcard later, but whatever came with the computer is probably adequate until you figure out what you're doing.
3) If you use a 4-track, without phantom power you're going to be limited pretty much to dynamic mics like the Shure SM57 or SM58 which run $80 -$100 or so I think. You can find cheaper mics but in general the lower the price the lower the quality.
Hope this helps - you'll get lots more advice about this from people that know a hell of a lot more than I do.