how can I extract the 'instrumental only' part

Date: 9 Jul 2003 21:25:40 -0700
Newsgroups: alt.music.karaoke
Size: 415 bytes

I think I have a nice voice and was in a musical recently in a local
theater and sang 3 solos in a Diana Kraal, Holly Cole sort of style.
I'd like to know if/how I could extract the voice and keep the
'instrumental only' part of a few recorded songs on some of my
favorite CDs so I can practice some new songs.
I'd like to do it on the cheap. I use Mac OS 9.2 and have the free
version of Quictime 5
Thanx much,