Not to hijack this thread (but I am). I hadn't heard of these books until this thread, and seeing your Lulu page, I am interested in buying at least two of the books (Directory of Demiplanes and Forbidden Arcana) shown. I do wonder how to buy these, through Lulu, or Ronin Arts? I could look at Ronin Arts, it wouldn't hurt, but which is easiest for you?
To be honest, I don't think the format is the problem, but the exposure. I have been to the Ronin Arts site before (actually via another website, suggested by Ashley Wood or Christopher Shy [it was a while ago, I don't recall which]), viewing the artist section. When I see .pdf I don't even bother 99% of the time, I want a print book. Had I known that you offered print gaming books, I would have purchased these long ago (or at least when they were released).
As for Lulu, can you print, say, ten books at a time? I am interested in printing an art book on my own, and printing out a mock up art book for a coffeetable proposal to send to an author. Any information would be great.