I thought this link might be useful for those trying to find a particular film or video. The Dance Film Association has an ENORMOUS and very detailed data base. You can search by choreographer, dancer, subject, composer -- many different ways. There are very detailed credits, as well as distributor/purchase information. (It's an informational database, not a commercial one.)

Here's the link to the database

And here's a link to the
Dance Film Association

UPDATE:
Here is a link to the Dance Films Association's website: http://www.dancefilmsassn.org/

They seem to have withdrawn their archives from the site.