I like a lot of the soundtrack of this game, but GOG doesn`t seem to have a download for it. Why?

Anywhere I can download the track?

If you go into the install directory: \Dream Pinball 3D\data\music

You will see a bunch of files with .wad extensions. I was able to play them in my media player no problems as they are
'Audio: MPEG Audio Layer 3 44100Hz stereo 192Kbps [Audio]'

Simply copy to preferred location, rename to .mp3 and you're good to go!