I have added links in the past to some websites that provide royalty free music. This solution is a little different, costs money but provides a more polished product. Sonicfire from Smartsound allows you to take their music tracks and through a series of manual and automatic features match the mood, tempo, instruments and volume of the musical piece to video clip, blending perfectly with narration. The embedded YouTube clip (sorry to those with no YouTube access) demonstrates the work flow of using both Premiere Pro (my preferred video editor) and Sonicfire Pro (also my preferred music integrator) to create a finished clip. Ironically the piece is about ReflecMedia green screening (also my preferred green screen technology solution).
For those of you who want to view this YouTube clip from home the link is http://www.youtube.com/watch?v=0PJlvqaTpxU&feature=player_profilepage
With educational discounts from Adobe meaning that the entire video productions suite costs around 400 Australian dollars, so, if you are ready to move up from movie maker, then this is a good combination. One gotcha is that that with the CS5 release of the video editing tools from Adobe, you need a 64 bit operating system.
