Visit the book’s website at http://pragprog.com/titles/mrhome, where you can download the code for all the projects, participate in the book’s discussion forum, ask questions, and post your own home automation ideas. Bugs, typos, omissions, and other errors in the book can be found on the book’s errata web page.
Other popular website resources include the popular DIY websites Makezine, and Instructables, where participants share a wide variety of home-brewed creations with their peers.
There are also several IRC channels on freenode.net and SIG forums on Google Groups dedicated to the subject, with many focused on singular aspects of DIY gadget design, home automation, and hardware hacking.
OK, enough with the preamble. ...