HELP! Mixer, Monitors, input limitations!

Hello, all you cakewalk experts!
 
  I was wondering, actually more like puzzling my  thin mind, about mixing, or the "output sound"...lack of better terminology.  Here's my quandry:
I have a fourpiece band, we like to record "live".  I know in MC4 you can only record 2 channels simultaneously.  We have the electronic drum kit going in midi,(thanx for the  remedy from yous' guys' on the last post of mine!) and that leaves a channel for the guitar, bass, or vocals.  All well and good.  I want to know how we can play "live" and record just one instrument into MC4, but still hear the whole band through the monitors?  We have no problem playing the song we are recording over and over so each member can lay down their part, but the log-jam is a problem.  I have an M Audio 2496 sound card.  Don't know if that has anything to do with anything...  My knowledge for mixers is as vast as the knowledge I hold of the flight patterns of male blue herons between 4-8 years in age, and have an unbalanced wing span.  Squat on both topics.  I was thinking a mixer could solve our problem.  we could all patch out from our amps into the mixer, from there into the reciever and on to the monitors for our hearing pleasure.  Like a P.A. so to speak.  Now.  Are there mixers where we can then send the signal for just one  instrument from the mixer to the sound card for recording, and out the same monitors?  Is this what a bus is?  Am I making any sense?  Is this possible?  Or is there an easy answer I am complety missing by overthinking as usual? 
Tell me what you guys do in your studios....Oh by the way, I'm poor and would like cheap fixes! 
Thanx in advance, because you do me no wrong, ever...
 
JD Scott

Thanx...
Are these mixers inexpensive?  What is the "Jargon" for these boards?  4 in 4 out?  something like that?  All our amps have line outs' so the mixer wold be cool for us.  I think uncle Google would be willing to help me find said mixers if I knew how to phrase them....

I'm wondering if the input limit applies to audio only, or all inputs, including MIDI?
Maybe you can try it, jd or Guitarhacker. I can't because all my working programs already allow more than 2 inputs.
Record your MIDI drums and 2 audio tracks at once, see if that works.

I think it refers to 2 tracks regardless of input type..... you can only have one midi track....well depending on the interface.... but yeah 2 tracks total input at a time..... next time on...I'll check it out but I'm 99% sure it's 2 tracks max at a time.