I got in a bit of trouble recently. I don't flourish much with cards but had been practicing a stage piece to a song by one of my favorite artists. It came time to perform, but I left the music behind. Copyrights were the big issue. Every single person said it looked like it needed music.
That wasn't fun. I also hope it's a little bit of warning.
Now I am going to repeat my stock answer with full justification. I make my own. I tried not being a snob and got burned. Now I'm going to look down my nose, which makes plugging all the gear into my mixer a lot more difficult. Then I need to start work on another new piece.
These days, the tools are cheap and plenty enough to make your own. You might also scour the Creative Commons for music that allows you to use in various situations as long as you provide attribution to the artist. I would warn you to fully understand those licenses before you jump in, however.