Associations / Organizations 

Associations on the Net
From the Internet Public Library. "A collection of over 2200 Internet sites providing information about a wide variety of professional and trade associations, cultural and art organizations, political parties and advocacy groups, labor unions, academic societies, and research institutions."

WANGO Worldwide NGO Directory
Links to over thousands of organizations. Search by group name, country, region, mission or group focus.

Scholarly Societies Project
Produced by the University of Waterloo, this site provides links to nearly 1,300 worldwide associations and societies, academies, federations, and other groups pursuing scholarly activities.

Idealist
Links to the homepages of over 16,000 non-profit organizations. Find organizations, jobs, internships, events and more, in 152 countries.