I heard from a reader last week -- let's make that, a listener -- who said, "Recently, I listened to your book which I downloaded from the National Library Service for the Blind."
While I couldn't find it during a quick search of the NLSB site, I suppose those readers with visual impairments will be more familiar with the process.
I am pleased, of course. Seven Wheelchairs was published through The University of Iowa Press which did not have the resources to make it immediately available as an audio book. I do hear some word that the Press may issue a Kindle version soon.