I think we've all probably seen more questions in this forum about door panels, dimensioned and otherwise, and headliners than any other interior topics. When it comes to door panels, creating the design, executing the design, and finally mounting the finished panel are probably the most common. As for headliners, I'd say the same applies - especially one-piece headliners.
I also think JeepTuff has a great idea about the DVD. Ididit might have a problem with a speaker recording and selling DVDs of a presentation at one of their events, but a DVD created at your shop might be something that could be considered. I'm not suggesting you take time out of your shop schedule to produce a series of videos on "how to do it yourself and thus avoid paying me to do it" videos. But maybe as projects come along at your shop that involve the more basic issues you see posted here could be covered. I.E. a short video on exactly how your shop deals with mounting a finished door panel on a steel-bodied car versus a fiberglass-bodied car. Or, as mentioned before, how you deal with upholstering around corners to avoid puckers and wrinkles, (I know this one - it involves CAREFUL use of a heat gun, and a bit of practice,) and tricky areas like hinges and door latches. Or even regular care and maintenance of our interiors once we have them finished and are driving our cars. Anyway, you get my drift.
I'm sure a local video production company (or even a friend with a good quality DV camcorder) could do the video work for you, and Lord knows I'd gladly pay $39.95 (plus shipping and handling of course) for a video demonstration of such knowledge. Anyway, it might be something to think about.
I've only seen photos of your work, Shawn, but what I have seen blows me away. I only wish I lived closer to Ididit so I could attend your seminar.
Kudos to Ididit for doing this every year, and for recognizing true talent in asking Shawn to be a featured speaker!