Like you should tar+gzip those songs and email them to razorm@gmail.com iago! I have to put together a presentation with a target audience in the same age group.
Just use Limewire. I found them all with ease.
AFAIK the best compression on mp3 files is rar. gzip and bzip2 fail to compare to how much space you can save. (the half a megabyte that is)
By design, MP3's already have really high ... bah, what's that word for randomness? Entropy? Something like that. Anyway, they don't have very many patterns to exploit so compression won't do much at all to them.