I think I'll be able to help you out. try searching "jazz jackrabbit soundtrack digiex" and choose the first result. the JJ1 and JJ3 tracks are still in their original formats, but with a little conversion to WAV by modplug player that's no problem at all. the JJ2 tracks are already in mp3, but the quality on lori central is a little higher, so my suggestion would be to download that there.

as for converting the WAV files to mp3, try searching free mp3 wma converter, again the first result (that is, in the Dutch google. I dunno about yours for sure).

if anyone is also interested in more music by alexander (these are in their original formats so could theoretically also be used for home cooked levels), I'll post a link to that later. because this is my first post on this forum (I usually hang out on a very small forum in which I try to promote JJ a bit as well) I can't post links yet.