Steve,
Visit www.flashgeek.com to view instructions on how to do this yourself.
Once you have inserted it, you might want to look at this free add-in
Flashback which will play/rewind flash movies automatically during
slideshow.
If you have difficulties doing it yourself, you could consider downloading
Toolbox www.mvps.org/skp/toolbox - an add-in which contain several utilities
including a Flash Movie Wizard which imports Flash movies into a PowerPoint
slide.