The Project Management wiki is at http://project-management.wikia.com/wiki/Project_Management_Wiki . It has over 250 articles about project management. Most of them are from the PMI/PMBOK perspective. You can use it and edit it with or without creating an ID and logging on. But you will see fewer ads, if you're logged on. The site has links to templates and other sites with PM advice. Your contributions would be welcome!

The Project Management Institute's Web site is at http://www.pmi.org . It has information about the certification, membership, templates, a job board and more.

There are also regional sites such as the Great Lakes Chapter's at http://pmiglc.org/index.php or the Tucson, Arizona chapter at http://www.pmi-tucson.org .

And sites selling training, including: http://www.pm-primer.com

Another useful site is the wiki for project management hosted by Wikia. It's at http://project-management.wikia.com/wiki/Project_Management_Wiki