HarperCollins did this inaugural seven part video series about the making of Lauren Oliver's The Spindlers. The first two videos discuss the author's process, then it moves into editorial, art, managing editorial, production, and the author reading. I already know a lot about the process of writing and editing the book, but I found the part about the art and the physical printing of the book very interesting, because that aspect is not often discussed.
Here's episode 4, about the art:
Here's episode 6, about the production:
You can find the rest of the video series at this link.