Dennis Paulson's Odonate Diversity
Giff Beaton's Odonata of Georgia
Gayle and Jeanelle Strickland's amazing scans
Ed Lam's page - buy his wonderful damselfly book, or just browse around his great site.
Odonata Central - look at a map of the distribution of any species in North America. Generate a state or county list. Submit a new county record. And much, much more.