I extracted the midi files from the Xeen games before, but they were in some custom format that nobody could read. If you are interested in those then I could help you out.

If you wanted mp3 versions, try running them in dosbox and recording "what u hear" using some audio program (I like Goldwave).

I think the MM3 music was created by The Fat Man, which would explain why you like it so much

MM1 and MM2 didnt really have music, besides that MM2 intro theme which was fairly boring.

Good luck