use google to search: flash <your actionscript version> video gallery
(i would think almost all of them are going to be xml driven.)
oops, i missed that. i didn't realize you wanted to create a youtube video gallery.
you most likely won't find anything that specific. you'll probably need to purchase or hire someone to do that for you.
if you wanted to do that yourself, you would need to check the youtube api for instructions on how to link to their videos.