Masters on Their Work: John Sturges and David Mamet

The John Sturges commentary is from the "Bad Day at Black Rock" Laser Disc release. And the David Mamet commentary is an edited compilation from unknown sources.

These clips are resources from a fantastic little blog that just got started called Film School Thru Commentary. There's a list of commentaries and quite a bit of other stuff already (first post is on Dec. 2).