Rohit: The .gog file in the directory has the soundtrack from the Definitive Collection. As for the original...well...
GOG version has a shorter 8 track soundtrack? I remember Definitive Collection version had 8 tracks, but several years ago I bought some probably german version of D2 (german cover and german manual in PDF, but game is still in english) and there is 12 tracks, 8 was in Definitive Collection too and 4 was new. These track was identified by freedb.org as: 04. Glut 08. Brian Luzietti , Crush 09. Mark Morgan , (untitled) 10. Type O Negative , Haunted It's bad, no addons and shorter soundtrack in GOG version. I'm little disappointed. I thought GOG version will be all in one. :(
Have a look here for the differences between the soundtracks. Basically the original release (which I have BTW) had 12 tracks, and the definitive collection had a remixed version with 8 longer tracks.
I have the original CD. The D2 Redbook audio is made up of 12 tracks, including the short title track. There are 4 midi songs that are played if you choose NOT to use the Redbook audio. That said, I can host everything somewhere if need be, however, I'm fairly certain they can already be found on the 'net. Email me at taylor.s.swann[at]gmail.com and I'll host the album for you.