there are generally no problems linking to other mp3′s found across the web.
for uploads to popround, putting up individual mp3′s of a song where you don’t own the copyright is not recommended. this site is a meant as a forum to spread the word about great music – not as a repository of freely downloadable mp3′s.
the way round this? we recommend building a mix (or playlist) of many tracks into a single mp3 – this makes it more difficult for visitors to save individual tracks.
also, if you dig out new or rare gems that few people know about, the artist/label/publisher will be more inclined to welcome the publicity rather than take umbrage at the free distribution. keeping it ‘underground’ will help keep popround alive.
look around – there’s a ton of legal free stuff available on the web. spread the word…