This thing has been in production since at least 1999. Selby recorded his part that year, shortly after finishing up Long Day's Journey into Night at Hartford Stage.
The video includes a featurette about the making of the program. The only actor whose recording session is featured is David Selby's. It also explains the use of multiple types of animation. I've seen a couple of posts where folks had commented that the animation looked rough. It's supposed to look the way it does, and co-producer/animator Brad Stalnaker also explains this on the video. Sometimes he opts for a very minimalist approach in order to draw attention to specific aspects of the characters. This isn't supposed to look like Disney.
The web site Julia99 provided is the official site for the production and includes all of the material that comes in the teaching packet. The producers received a National Endowment for the Humanities grant, and a lot of time and effort went into perfecting the teaching materials.
The site also includes photos of David at one of the premieres.
If that's not enough to keep you occupied, visit my Selby site (link banner below), and check out the News page for all sorts of links to information about The Griffin and the Minor Canon. I've got some additional photos from the Charleston premiere. I also have some screen grabs on there from the production as well as from David's recording session. His father was present during the session, and you can see his reflection on the glass over David's face. It's a very interesting visual effect, though it was unintentional.
C.