The KML Handbook: Geographic Visualization for the Web, by Josie Wernecke, Addison Wesley 2008
Josie Wernecke provides an excellent description of all of the features of KML (Keyhole Markup Language). This book serves as both an introductory guide and a reference for KML practitioners.
Josie Wernecke is a senior technical writer for Google, and this shows. The book is well written, and laid out. Unlike the KML reference manual on the Google website, the logical layout and presentation should aid the reader.
Wernecke targets a range of reader expertise. She describes simpler things like alpha, hexadecimal colors, and CDATA tags; but does not make the mistake of spending half the book describing these more basic concepts.
The examples are also interesting - or they are for someone with a couple of degrees in the natural sciences! Examples include archaeology, volcanology, seismology, primates (the Jane Goodall Institute), urban geography; in additional to the obligatory hiking / travelogue examples.
The book is in full color. Although this is unnecessary for the main text, it does help some of the screenshot images. A full KML reference comparable to the online version is provided in an appendix.
This book is recommended for all KML practitioners. It will be a good book for someone trying to learn KML, but should also be useful for someone who is more experienced. The geospatial web currently contains a surprising number of ill-formed KML files, and this book should help to remedy the situation.