What is the 'center button'?

First of all, it's not a dumb question! (the only 'dumb' question is the one you don't ask!). I don't know what they mean either by the 'center button'.

But I think the only way to add lyrics is to do in in iTunes and then they get transferred to your iPod. But I could be wrong.

I can't even figure out how to see lyrics in the iOS Music app. Any help?

The reference to the centre button refers to the iPod Classic, so the article is poorly written.

The method it mentions for adding lyrics is correct.

1. In your iTunes Library, highlight the song and selct File/Get Info/Lyrics
2. Paste the lyrics into the lyrics box and press OK
3. Sync the iPod with your iTunes library (for the change to be added to your ipod). This asumes that you are using Sync, not manually manage.

On the iPod Touch, to display lyrics that you've added to a song:

1. In Settings/Music>Lyrics & Podcast Info, make sure this is "on".
2. The lyrics will show up when the Scrubber Bar (time played/remaining) is displayed.
3. If the lyrics (and Scrubber Bar) are not showing while the song is playing, tap the screen.

Glad to have helped.