There's a goldmine out there, often of programs that were once issued for sale on video cassette, that have not reached DVD for re-issue.
I gather licensing is one of the big problems
I'm not sure if I remember The Midnight Special series, but if it was live, would be great.
Recently I found something called : "So you wanna be a Rock n Roll Star" of appearances on THE BEAT GENERATION (1967-72). I'm assuming that was a British TV show?
The Ed Sullivan Show releases of the past year were panned, and what I read about them was depressing - some lip-synched material, incomplete renditions, etc.
Edit - While I was typing I guess Douglas posted - I do remember "Don Kirchner Presents"