The original soundtrack has been composed by Barry Leitch. The audio on the PSX CD is stored in XA tracks, so it doesn't sound so good. But when I contacted Barry Leitch to know if I could make the MP3 that I had made from the game CD available, he told me my MP3s didn't sound good enough and he sent me the soundtrack himself, recorded from the source :-)

So here is the original Spider soundtrack, from the author himself. My personal favorite is the Sewer track.

Bonus
Brain
Credits
Dinosaur
Egypt
Evil Lab
Factory
Factory 2
Lab
Lab 2
Lab Boss
Map
Museum
Options
Sewer
Street
Street 2
Surfin