1. The music is on YouTube if you just want to hear it there -
https://www.youtube.com/results?search_query=humongous+soundtracks

2. If you want to extract the music yourself, I've prepared an explanation below.

First off, total thanks goes to Barnstormer on the Lucasforums for the music extraction software.

http://www.lucasforums.com/showpost.php?s=8b1ba4713ed0406b4521caccd99c5442&p=2787924&postcount=17
http://www.lucasforums.com/showthread.php?t=191740

1) Download the tiny "He_games_music_extractor" on Mediafire or as the attachment below. (Of course change the ".jpg" to ".exe" in the case of the attachment.)

I encourage you to back-up this software and share it to keep it "floating" around the web.

2) Open up Barnstormer's extractor. (IIRC, you may need to install Microsoft NET framework for this software to work.)

3) For "Game Music File (.He4), browse to the game from which you want the music, then find the one file with the .HE4 extension. (For example, C: -> GOG Games -> Pajama Sam 1 -> PAJAMA.HE4 )

4) For "Extraction Dir", browse where you want to extract the music, like a folder on the desktop. WARNING: You can expect dozens of music files.

5) Click "Extract" and wait until everything is done.

If everything goes well you should see lots of "stream" music files (stream0, stream1, etc.) in the WAV format in the extraction folder. For example, Pajama Sam 1 has 56 music files, most 0:30 sec to 1:00 in length. Short but sweet nostalgia I think!

Let me know if I missed anything or should make any changes. I genuinely hope this is helpful, though.