There are a few programs that will automatically grab the lyrics for you and embed them into the mp3 file for you. Less that I know of that will grab the lyrics and put them in a file named the same as the song in the same folder as the song.

For an example, of the latter. There's a lyrics screenlet for anyone that uses screenlets (imagine Widgets). If works with most default music programs in Linux (Amarok, Banshee, RhythmBox, etc..) and it'll grab the lyrics of whatever song that's playing and put it into a folder named the same as the song file name (e.g. if it's bob then the lyrics will be in a file named bob). Then I just copy and paste it into there.

But there are also programs like Minilyrics which will grab the lyrics and integrate them into the mp3 file automatically.

If there's another solution I am unaware of for easy populating of lyrics then please let me know. And I will have info on how lyrics are done (when integrating into mp3 files) soon (just need to boot into Windows sometime since Minilyrics is Windows only).