I just rented Standing in the Shadows of Motown on DVD and it was not a bad documentary. If you grew up hearing the Motown sound, or if you grew up anywhere near Detroit, this may be of some interest to you.
The film documents the role of The Funk Brothers in the Motown sound during the 60s and into the 70s. I'd never even heard of these guys, which was the basic point of the film. They backed many (if not most) of the Detroit-era Motown names, and did all the heavy lifting for most of the hits.
The guys who are still alive from the 'lineup' reunited at the Royal Oak Music Theatre (Royal Oak MI) in 2002, where much of the documentary was filmed live. But in addition, the guys get together in the so-called 'Studio A', Hitsville USA studio in Detroit to recall the glory days. Some old film footage, some great stills and thankfully, only 2 or 3 reinactments, bring back images of 60s Detroit. Great stories about their out-of-the-studio experiences in the Detroit jazz clubs and clubs they played around the country.
Anyway, these guys did all the music behind the vocalists, and never appeared on the credits on any of the albums until around 1970, I guess.
If the only radio station you could get as a kid was CKLW out of Detroit, then you might want to take a look at this long-overdue tribute to some great musicians who made it all happen. It made me get all weepy.