International Celtic Congress - Founded in 1902 to promote the knowledge, use, and appreciation of the Celtic languages and cultures. Includes an organization constitution, events and contact details. - http://www.evertype.com/celtcong/cc-home-en.html
Celtic League - Official site of the league's American branch. Provides information on the languages, history and culture of the Celtic Nations. - http://www.celticleague.org/
The Celtic League - Organization that campaigns for the social, political and cultural rights of the Celtic nations. Includes branch addresses, objectives and membership information. - http://www.manxman.co.im/cleague/