I've had the same thing happen more than once - click on a song and be told it's not there. When I did a search for the song (typed a part of the song or title into the search box) as opposed to using the alphabetical (go to the search box and click on a letter) listing, I had no problems. Wish I'd paid attention to what the songs were, but I was short on time. Will do next time I find one that "isn't there."
This doesn't happen very often. Of course, if it happens for every song you click on, and other Netscape 4.77 users have no problem, it's not the website that's broken.