Hello,
I'm just wondering if there is a way you can take your favorite songs, take out the lead singer and make it into a karaoke song? Thank you very much!
Yes, more or less. Lead vocals are usually "placed" in the centre of a stereo mix. My grasp on the physics is shaky, but as I understand it you can essentially "subtract" the left channel from the right (or vice versa), thereby removing anything in the centre (including the lead vocals). There'll be a consequent effect on things panned to various degrees off-centre. Also, reverb in the original mix might foul things up a bit.
I've looked over a guy's shoulder as he did it – attempting to remove dodgy trumpet, not generating karaoke tracks! I think the software on-screen at the time was Pro Tools, but as to whether this function was carried out by the main program, a third-party plug-in or something else altogether, I'd only be guessing.
You'd probably also want to give some thought to the copyright issues, particularly if the intention was to use such tracks in public.