I think SongMaster Pro works fine for producing backing tracks to sing along to (at least it works fine for me).
Just drag in the song and split up the stems in the mixer and just mute the vocal.

Just tested the Music Separation in Audacity (vocal, and the rest) it seems to work fine as well.
But SongMaster Pro is so much more and makes singing to the extracted mixed backing track so much easier with the options to add in the lyrics at the exact timing locations. As well as showing the lyrics in the time line, could also as well be shown in a lyrics window or karaoke window (trial version is available).