Use youtube to find the song(s) you want, copy and paste the URL to this site: http://www.youtube-mp3.org/
download file and you can add it to your media library.
I use that site often, baby doll, but I find I get mixed results in terms of the quality of the mp3 that is produced. Some mp3's are decent and other the sound is dull/flat.
Install Torrent (do the custom install, and don't install any of the 3rd party software/ad-ons)
Install peerblock (so you don't get noticed by the RIAA, etc)
Search pirate bay for whatever you want.
Pucky. I have a pretty large collection of .mp3's. We can discuss which ones you may want and if you send me a USB key or two, I can fill em up with a bunch of anthologies from whatever groups you may like that I have... I have in the neighbourhood of 150 gB of tunes