Graphic arts has been a hobby of mines for years. However, I created my first book trailer with a few applications that came with my computer. Windows Movie Maker 2.6 and PowerPoint 2007. I also used a few of my own photos and some stock photos available online for free. Check out my trailer. http://www.youtube.com/watch?v=R278-x-tBio
I have tried several video editing programs. Sony Vegas Movie Studio 9 is far and away the best I've tried. It is stable--never crashes--which is almost unheard of for an editing program. It also has a large customer base, online forums, and numerous online videos that show you how to use the program.
It's actually pretty easy to make book "trailer" videos yourself, for free. I have an ebook manual that lays it out and includes massive links to online resources for free programs, music, film clips, support, etc.