Depends on what kind of "track" you mean.
If you mean "track" as in tracker-music (as used in JJ2) the answer is: yes.
Links to check out:
ModPlug
United Trackers
Trax in Space

If you mean "track" as in track-recording or sequencing (as used in studios) the answer is: yes.
Links to check out:
Maz Sound (browse through the utilities)
No Error - search on sequencers
and many other free software sites.

However, the latter form of music is not (directly) usable with JJ2, if that's your goal. Enjoy!