It turns out the idea of a custom book is over 40 years old. M. McLuhan predicted such a thing would exist waaaaay back in 1966, during a television show called This hour has seven days. He says:
Instead of going out and buying a packaged book of which there have been five thousand copies printed, you will go to the telephone, describe your interests, your needs, your problems, and say you're working on the history of Egyptian arithmetic. You know a bit of Sanskrit, you're qualified in German, and you're a good mathematician, and they say it will be right over. And they at once xerox, with the help of computers from libraries of the world, all the latest material just for you personally, not as something to be put out ona a bookshelf. They send you the package as a direct personal service. This is where we're heading under electronic information conditions. Products increasingly are becoming services.
A bit earlier, in a different interview he says
The future of the book is very much in the order of book as information service. Instead of the book as a fixed package of repeatable and uniform character suited to the market with pricing, the book is increasingly taking on the character of service, an information service, and the book as an information service is tailor-made and custom-built.
(source: Understanding Me, lectures and interviews. Marshall McLuhan. Edited by Stephanie McLuhan and David Staines. MIT press, 2003. 305pp.)