OMG’s BPMN website. Besides the official BPMN specification, there are some introductory articles, examples, and web links.
BPMN Poster
A poster with a BPMN 2.0 overview. Available in many different languages. Created by BPM Offensive Berlin.
http://www.bpmb.de/index.php/BPMNPoster
BPMN Tool Matrix
Comprehensive list of BPMN tools with information such as supported operating systems, release dates and license types.
Method & Style
Bruce Silver’s weblog on about BPMN and related standards, such as DMN (Decision Model and Notation) and CMMN (Case Management Model and Notation).
http://methodandstyle.com/blog
Workflow Patterns
Homepage of the Workflow Patterns Initiative, coordinated by Professor Wil van der Aalst (Eindhoven University of Technology) and Professor Arthur te Hofstede (Queensland University of Technology). Here, descriptions of differrent workflow patterns can be found, as well as articles on how to model the patterns in BPMN.
http://www.workflowpatterns.com
Groups in Social Networks
There are several BPMN-related groups in LinkedIn, XING, and Facebook.