The overviews of both TAPI and the TSPI included with the platform SDK are excellent. They were an immensely helpful resource in my understanding some of the more obscure parts of TAPI, as well as helping to track the changes from one version to another. I also recommend several resources on the Internet. If you post a question on one of the newsgroups, it's likely that one of these two guys will be providing the answer. I thought long and hard about providing the source as a set of appendices for this book and ultimately decided against it.
Printed source is sometimes useful for understanding specific implementation details.
As these details come up, I tried very hard to put the significant source into the text of the chapters themselves. As my favorite books are of the thin, focused variety, I found this unnecessary bloating unappealing to me. Plus, I may save a few trees in the bargain. This book is the concentrated effort of many individuals. First, I want to thank my wife, Melissa.