Where can I find karaoke Christmas music?

First, let me explain. I’m thinking of Christmas songs where the vocal line has been taken out, just the instrumental remains. Or, if there is a choral accompaniment, then where the chorus remains, but the main vocal line has been taken out.
I’m thinking it might be fun to download these to a CD and sing with friends. If these songs can be downloaded from the internet, that would be best. If they are available for purchase, it’s too late for this year, but I would consider this option for next year.
Of course, I don’t want this to be limited to just Christmas music. Can one find karaoke versions of other songs as well, available for downloading?