Project Management Institute. A Guide to the Project Management Body of Knowledge (PMBOK Guide), 2000 Edition. ISBN 1880410230.
The PMI Bookstore (www.pmibookstore.org) Offers general project management reference materials and other self-study texts.
PMI eLearning Connection (www.pmi.org) Offers virtual, online seminars and study programs.
Commercial PMP Prep Courses Search PMI (www.pmi.org) for a listing of PMI Registered Education Providers that offer PMP exam-prep courses. Many of the courses are now offered "online" and better support your lifestyle.
Project Management Institute. 
The PMI Bookstore (www.pmibookstore.org) Offers general project management reference materials 