This thread seems to have drifted into a discussion on copyright, and the usual confusion this brings.

Almost any copy, whether as a backup, transfer from LP/cassette, ripped onto an MP3 player or whatever, is likely to be illegal. Will you get sued? Highly unlikely - what is the financial loss to the copyright owner? Only the cost of another CD or download which you should have bought instead, not worth picking up the phone to the lawyer over. But if you're going to start selling bootlegs, or making the files available to download, then they'll go for you.

The copyright on a songbook covers the printed arrangements. If you want to photocopy the sheet music, you need the publisher's permission. If you perform or record those songs, then you owe a separate royalty to the songwriter (or copyright owner), usually collected by one of the copyright agencies (PRS-MCPS in the UK) from fees paid by the venue, or prior to the album being issued.

If you like someone's music and want to put it on your blog or website to spread the word, that's still unlawful - you're giving away something that's not yours to give, even if your motives are good. You should link to their website instead. If you're determined to play their music on your site, you need their (or their record label's) permission, again usually handled by one of the copyright agencies who will gladly sell you a licence to do so.

Whether copying is morally wrong in all these circumstances is another matter. Copying a CD you've purchased onto your MP3 player? Not in my opinion. Copying an LP which isn't available on CD? Again, OK in my opinion. Copying an LP instead of buying the CD re-release? Not acceptable, the copyright owner is losing out. But these are my personal views, and don't alter the fact that all of these actions are breaches of copyright.