How do I add lyrics to a song in iTunes so that it shows the lyrics on the iPod/iPad?
Right click the song in iTunes and choose Get Info. Second from the right is the section "Lyrics" where you can paste the lyrics of the song. The lyrics will show up on top of the album art when the song is played on the iPod. Tap the album art to show it if you don't have all the controls visible.
I own iClip Lyrics and I was fortunate enough to download it before they discontinued it. (It still works even though they aren't developing it, and if you can find it online I highly recommend it)
All you had to do was play a song, it would search the internet, grab the lyrics, and automatically add them to the ID3 tag for the the MP3 file.
There are some other apps out there that do basically the same thing:
I've written a post on my blog to showcase my findings regarding this question. Check it out:
To add lyrics to a song, I use this dashboard widget: TunesTEXT
Very simple but very useful.