Can anyone give me a link to a method of creating some of these other sound formats - MOD, XM, etc - are they lower quality? lossy, lossless? pros/cons? thanx

MOD and XM are similar to the MIDI format. I'm not sure, but I think they pre-date the MIDI format. You're better off going for the MIDI format.

As for getting a converter, you can't convert Mp3's to MIDI because a MIDI file is a sequence of instructions, not actually any sound. That's why they're so small.

An MP3 would correspond to a recording of the music.
A MIDI would correspond to the appropriate sheet music.
A MOD would correspond to the sheet music plus recordings of each note for each instrument.

MIDIs are very small, but will sound different depending on the machine, have to be sequenced, and can't contain vocals. MODs are moderate sized and sound the same on all machines, but have to be sequenced, and can be tricky to do vocals. MP3s are large, sound the same on all machines, and can be generated from most any input.

I've got a little program that converts between audio and video formats quite nicely, haven't tried it on MIDI's though. It's called mediaconverter, can't remember the site, google it. It's nice for turning wma's to mp3's and flv's to wmv's, so I can rip tons of stuff of youtube and put in on my phone I'm naughty.

I use Total Video Converter. It does anything to anything, even Real Media.
Only problem is, you're supposed to pay for it...

*ahem* Supposed?

I regularly use Total Video Converter, Blaze Media Pro, Xilisoft Video Converter, and Xilisoft Audio Converter.

The TVC and Xilisoft apps are top notch, and no, I won't pay for them.