Filmstro is something of a unique service when it comes to music. With plugins for both Premiere Pro and Final Cut Pro, you can pick your music and then use sliders to adjust the momentum, depth and power of that music throughout your clip. You can adjust any tune to match the mood of your scene as it changes from shot to shot.
But they have static versions of all their Royalty Free music, too, and they’ve just released them to the world for free for use on YouTube. Even if your video is monetised.