Canadian Advisory Committee on the International Standards Organization’s (ISO) work towards standardization in the field of Project, Program and Portfolio Management (PPPM).
Software Project Managers Network, established to encourage good practices in acquisition projects for the US Department of Defense. Purchase your copy of Risk Radar and Project Control Panel dashboard, as well as there are free books available.
Association for the Advancement of Cost Engineering will be of interest to engineering/construction project managers. They have a good bookstore, and they offer the new Earned Value Professional (EVP) and Planning and Scheduling Professional (PSP) certifications.