"The Definitive Guide to Plone is the authoritative, unique guide to Plone, describing everything from installing Plone (on Mac OS X, Windows, and Linux) to writing code for the system. The book - part of Apress library of Python programming and content management tools, and written by one of Plone core development team - emphasizes the customization of Plone, and shows how to fully integrate Plone into an existing Web site and application. If you want to adopt Plone for some or all of its features, this is the book to pick up and learn by.
About the Author
Andy McKay is a principal of Enfold Systems and an active contributor to a variety of Python-based open source projects. He is also a core developer of the Plone content management system. McKay maintains ZopeZen.org, a website dedicated to Zope-based applications and Zope extensions."
http://www.amazon.com/gp/product/1590593294/sr=8-1/qid=1143468508/ref=pd_bbs_1/102-7040672-3156910 [en]
http://docs.neuroinf.de/PloneBook/
http://plone.org/documentation/manual/definitive-
guide/definitive_guide_to_plone.pdf [pdf]