British Bryological Society
http://rbg-web2.rbge.org.uk/bbs/bbs.htm
The Society exists to promote a wider interest in all aspects of bryology. It provides tuition, organizes meetings, facilitates research and aids measures for conservation.
American Bryological and Lichenological Society
http://www.abls.org/
This Society is an organization devoted to the scientific study of all aspects of the biology of bryophytes and lichen-forming fungi.
Canadian Botanical Association
http://www.cba-abc.ca/cbahome.htm
The Canadian Botanical Association (CBA/ABC)serves as the national organization for botanists in Canada, including professional botanists at universities, colleges, schools, government and industry as well as students, technicians and amateurs. The association represents Canadian Botany and botanists in matters of local, national and international importance.
Intute
http://www.intute.ac.uk/biologicalsciences/
Intute offers free access to a searchable catalogue of hand-selected and evaluated, quality Internet resources covering the natural world, co-ordinated by 7 universities of the United Kingdom.