One of the top sites on the web for Birdwatchers is the National Audubon Society webpage. A big advantage to the site is the fact that it has links to all the individual State sites. The Birds of Audubon section is amazing and contains many beautiful painting by John James Audubon. There are also sections based on actions being undertaken by the organization. An example would be the section on the status of the Upper Mississippi River. The site is a model for what a non-commercial, user friendly site should be like. WRMN gives this site a top recommendation.
The American Birding Association is a non-profit organization that publishes a number of periodicals. One of the interesting aspects of the site is their lising of Birding tours. A major theme of the site is conservation and many resourses and suggestions for advancing the cause are included throughout this excellent site.
The Cornell Lab of Ornithology is another great non-profit with a presence on the web. Take their virtual tour as see the lab inside and out. Their nestcams are also very interesting and reveal the lives of birds in a very intimate way. They even offer sophosticated home study courses to help increase your understanding of all aspects of birding.
The Digital Photography Review site contains a wealth of information on photography and cameras. Currently most of the photographs taken on the WRMN site were captured with a Nikon D70 and here is another excellent review by Thom. New photographs on the site will be taken with the Nikon D2x and here is a review of that camera from Bob Atkins. The Digital Photography blog is filled with tips on photographing birds.
FatBirder is a gigantic free site. Their listing of the Top 500 birding sites is amazing. A visitor can easily waste several hours following the links from this site.
The Wikipedia is an online encyclopedia that is free to use. It is a wonderful resource. Here is a link which resulted from a search for "Robin", which give a photograph and quite a bit of detail on this very common bird. Wikipedia is unusual in that it is built and changed by its users.
BirdingGuide is another online birding site. The guide provides detailed information on the particulars of making birding trips and making proper identification. We like the narrative of actual bird watching trips that are recorded on the site.
Ebird is a bird sighting tracking system sponsored by Audubon and the Cornell Lab of ornithology. Participants can submit and view sightings from around the country.