Looks like an interesting piece of software, but I'm rather interested in music from the early days of PC soundcards ('88-'92) before the advent of CD-Audio and General Midi, which are both well covered on the web.
While there are Adlib archives, none of them can be called exhaustive. There is also virtually no music generated by CMS/Gameblaster, PC Speaker or other more exotic hardware available. Also MT-32 pages are mostly specialized (like the excellent Quest Studios page) or simply small.
Compared to the amount of coverage of SID music or NES/SNES and other consoles PC music from the early days receives very little attention. Perhaps this will change in the near future. I'm under the impression that many retro gamers are acquiring original sound hardware which was too expensive back then (like the MT-32) and which was mainly bought by musicians.