Worldwide Scout Associations

World Scout Bureau: http://www.scout.org
Kandersteg International Camp Centre: http://www.kisc.ch
UK Scout Association: http://www.scoutbase.org.uk
Baden-Powell House, London: http://www.scoutbase.org.uk/direct/campsite/bphouse/
Brownsea Island: http://www.brownsea-island.org.uk/
Places to Camp in the UK: http://www.ccsw.org.uk

Others
BSA Booklet on Exchanges and hosting Scouts from other Scout Associations: BSA Tours and Exchanges