Thanks for replying, pone.
Well, given that such a database would have to display, on one single page, tens of thousands of tracks to be at all effective, I guess that rules out a tag source script.
Is there any alternative to this method, though? Looking through this forum, I've noticed that one particular user (ResidualImages), has created a programme that finds lyrics for whole batches of songs, which he integrates with Mp3Tag by way of the "Customise Tool" function in Options. The method is explained in more detail in the help document that comes with the download, found here.
Assuming that the database from which this app acquires the lyrics from uses multiple url's, it should in theory be possible to apply the same method to the problem at hand. I'm no programmer though, so I don't know how practical this would be to make. I'm guessing it's a lot of work though. What do you think?