I've got the recordings of a two-day workshop sponsored by PTC last year available - thanks are due to IBM for providing my time, PTC for recording the workshops, and to OASIS for hosting the recordings and sample files:

Day 1 is an introduction to DITA, followed by authoring and information architecture best practices and demos.

Day 2 is an introduction to specialization, followed by a series of practical demonstrations.

These are not professional-quality recordings: there is futzing around with phone lines and lots of questions and answers. If someone feels like doing an edit to split it into smaller and more usable chunks, I think that would be awesome - just add the edited versions to the existing resources post. I realize the current files are huge and cluttered with procedural flotsam. But in the meantime there is a lot of information packed in there, and the good news is you have a fast-forward button, which realtime attendees would have probably traded their laptops for.