Excellent, thanks Joe.

I forgot to mention the van Basco player is free, and you can do other great stuff with it like transposing (if you want it played higher or lower), and speeding up or slowing down (if you prefer a different tempo) just by moving a slider.

There are other excellent free midi tools about too, one of my favourites is synthfont (www.synthfont.com) with which you can do even more stuff - change soundfonts and instruments, change the mix (bring up some instruments, make others quieter), and most importantly output the tracks to separate .WAV files. Then if you want you can load it all into the excellent, free multi-track "recording studio" audacity (www.audacity.sourceforge.net/) , add voice (however many tracks you desire - do your own harmonies!), add effects, remix if desired, and output to stereo mp3.

If you want to edit the actual midis other free tools are better suited e.g. Quartz Audiomaster, Anvil Studio (refer google).

So you can do high-quality multi-track recording now for the cost of a decent microphone, or for free if you've already got a mic. Incredible!