Well, IIAL, albiet one that doesn't practice in IP, so take this with a grain of salt if you must.

Anyway, there is a great deal of misunderstanding about the legality of posting chords & lyrics. In a nutshell: chord progressions are (probably) fine, but lyrics are most definately NOT. I say "probably" because I am informed that there is a US Supreme Court or USDCA case out there that has ruled that chord progressions are not copyrightable. I have not seen this case, and it seems to me that there ought to be just as much creativity in an interesting and unique chord progression as a unique melody, but that's just me.

As for copywritten lyrics, that's absolute: you can't do it, and anybody who tells you that you can is either lying outright or fooling himself. It makes no difference whatsoever whether you're doing it not-for-profit or not. You will occasionally get people arguing this, but its really a non-starter -- the copyright owner is the only one who can make copies or approve of copies being made for free. All others must pay royalties. There are some limited exceptions under the "Fair Use" doctrine, but I would have to spend way more time on that than anyone here is likely to want to read.

The above is specific to US law; UKians, sorry, but I don't know your interpretation of the Berne Convention well enough to comment.