Update: Elonka’s Code & Cipher Book
Elonka's book is out, in the US as The Mammoth Book of Secret Codes and Cryptograms (in the UK it will be called The Mammoth Book of Secret Code Puzzles), by award-winning code-breaker and game developer Elonka Dunin. She's got a page up on her site with more information about the book and links to purchase it on Amazon.
