National

• North American Bluebird Society
• Sialis.org         (This website is packed with information on Bluebirds)

Minnesota

• Minnesota Audubon
• North Woods Audubon Center
• Saint Paul Audubon

Other States

• Bluebird Restoration Association of Wisconsin
• Bluebirds Across Nebraska
• New York State Bluebird Society
• Ohio Bluebird Society
• Michigan Bluebird Society

Other Sites

• Bluebirds
• University of Cornell, Lab of Ornithology