Ajax in action / Dave Crane, Eric Pascarello; Manning, c2006.
Professional Python frameworks : Web 2.0 programming with Django and TurboGears / Dana Moore, Raymond Budd, William Wright.
If you are developing web applications using Python you will want to use a framework so you are not re-implementing all the ‘glue’ that is common to all web apps and so you have a clear project structure to work around. This book is an excellent introduction to two frameworks, TurboGears and Django.
More info is at the Library of Congress