There is a surplus of sudoku books available at most bookstores. They all have one thing in common: they have a zillion puzzles, sometimes prefaced with a scant 2-3 pages of how-to. The how-to is usually not much more than a route set of rules to follow, with little real explanation. Books that actually get into the theory, logic, and design are virtually nonexistent. I have my own skeptic reasons for why this is the case–similar to the “give the man a fish vs. teach a man to fish” line of reasoning. Why give out the secret to creating sudoku when you can instead create a bunch yourself, bind them in books, and sell a bunch of different books?
Some time, in recent memory, I did see a book up on a shelf that did get into the mathematical theory of sudoku as well as algorithms for creating puzzles. Unfortunately, I do not remember where it was, what the title was, or who the author was. Amazon searches have found exactly one book, primarily focused on Visual Basic. The reviewers are a bit critical of the methodologies (solving by brute force, creating using only 4 strategies), and I’d really rather not have to mentally translate VisualBasic to any of the C-based languages that are available to me (C, C++, Java, PHP, etc.)
There has to be a decent book on the subject out there. I just cannot seem to find it.