I looked into this a while ago, but the results are disappointing: http://www.anunrelatednote.com/?p=52

Why aren't these games digitally available yet? The demand seems to be in place, so related parties are bound to make a few more bucks this way on these relatively old titles.

I'd strongly encourage anyone who hasn't done so yet vote for the Jazz Jackrabbit titles be released in some sort of downloadable form. Especially GOG.com seems like a likely candidate; go to their wishlist page, search for the Jazz Jackrabbit entries and nominate them for a release. (though it's odd to see requests for Holiday Hare 94 and 95 on there, as they were released for free as shareware episodes)