The source code from the examples can be found in our code repository.
You can also find the major modules from the book listed by name here.
We also have all the code wrapped up in both a tarball and zip file, in addition to a Cookbook.ppd ppm package for Win32 users.
While we have tried to make all of our source code freely available, we may have missed an example or two.
Feel free to contact us with requests for missing examples.