Deepal Jayasinghe has published a book on Apache Axis2.I think this is the first book, dedicated to Apache Axis2. Deepal has been a contributing member of the Apache Axis2 project since it's origin. He is an architect and a developer of Apache Axis2 Web Service project. In addition to Axis2, he has made major contributions to Apache Synapse, Apache Axiom, and Apache XMLSchema projects. Deepal has written more than 30 technical magazine articles, research papers and has delivered speeches in various SOA and Web Services conferences. He is a Apache Web Services PMC member as well.
You can check out his book here.