Hi
Two that I particularly like are:
"Set the Piano Stool on Fire", which is a documentary featuring Alfred Brendel and his protege Kit Armstrong. Not sure it's on Youtube, but you can (or could) buy the DVD.
"Mike Garson & his 88 friends", which is a documentary about Mike Garson, the Pianist who recorded on the most David Bowie albums, and played live with Bowie more than anyone. Don't think this is just a documentary about another pop Pianist. Mike Garson is a true virtuoso in both Jazz & Classical. Again this is (or was) available on DVD.
Here's the trailer:
Here's the full film:
Cheers