You might check out n-Track
http://www.fasoft.com/
It's $49 to register the 16bit version, $75 for the 24 bit (If you ain't got a 24 bit soundcard, don't bother with the 24 bit version). People either love it hate it. I'm in the former group. Never had a problem with it...does everythin' I need it to do. As long as your soundcard has mic, line, and midi inputs, you should be good to go. From what I understand there are other cheap programs that do midi a whole lot better, but I've never had any problems with it. Then again, I don't use a whole bunch'a midi.
The good thing 'bout the cheap price is that you'll have more money to spend on other goodies such as mics, mixers, preamps, etc...
hth
