I don't think I'll ever find the time to annotate every link, but this is nevertheless one of the biggest lists of stuff on the World Wide Web that is of interest to record collectors. Several more or less rabid collectors also have their own home pages. Some of them even hunt in packs. The two major collectors' magazines have their sites, but not a lot to offer there. Record Information Services Hot Wacks, the bootleg information clearinghouse of the past, is now alive on the net.
Many useful discographies are also available on the net.
Masanori Yokono's Beatles Record Collection Beatles trainspotters are very well served by these sites. These database programs, for UNIX, Windows and Windows respectively, look very good, but I don't have machines powerful enough to run them. And, last but not least, collectors of recordings have their Usenet newsgroups.