There's some stuff on YouTube but it's not comprehensive.
The trouble is that by making vids available to the public people and manufacturers open themselves up to litigation should anything go wrong - we live in a risk averse society now. It's a bit like a doctor putting out a vid on, "how to diagnose and operate on a burst appendix." Scary stuff.
Your question is very wide - you want vids on everything?
Peccavi
August 2009