This is an excellent book. Web Services is a very new area of distributed computing, and as anyone who works in a client server environment will know, setting up your environment is half the battle. This book walks you through the world of web services, from setting up your environment, to publishing the web service using UDDI.
From my experience in web services i have come to the conclusion that there are 2 ways to connect to a service, a direct connection using the apache.soap api, or using WSDL to create stubs and skeletons...very similar to CORBA and IDL. This book covers both methods extensively.
If you want to buy one book to learn the ins and outs of web services, then this is the book for you.