what programs (preferably freeware) can synchronize a video recording with a seperate audio recording?

Question by Pian-o-matic: what programs (preferably freeware) can synchronize a video recording with a seperate audio recording?
I’d like to make a youtube video of me playing a piano piece (yeah, I know, I have too much free time), but I have a microphone that is much better than the one on my webcam. I can disable the webcam’s microphone, but is there a way for me to synchronize the sound and the video files? I tried windows movie maker, but I can’t seem to synch it there (my fingers and the notes always eventually go out of synch) I guess I’d have to do it manually in the worst case… Thanks in advance!
Or what could be even better is a recording software that can take input from the video camera and audio from the microphone…?

Best answer:

Answer by Apolo
I have used a few video editing programs and the easiest one has been DVD Slideshow Builder. Very easy to use with professional features and same sort of layout as Movie Maker however a lot more powerful.Everything is laid out in an easy to follow step by step instruction.
Highlights:
Edit photos and videos with built-in tools, like crop, rotate, apply effects, etc
One-click to auto-synchronize video and audio
http://www.ourpix.com/dvd-slide-show.html#150

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