About.com
A useful set of links and articles from the ever reliable editors of About.com.
http://birding.about.com/

American Bird Conservancy
Concerned with conserving wild birds and their habitats throughout the Americas.
http://www.abcbirds.org/

American Birding Association
Online resource for birders of all levels.
http://www.americanbirding.org/

BBC.co.uk
Listen to birdsong from around the world.
http://www.bbc.co.uk/nature/programmes/radio/dawn_chorus/

Bird Observers Club of Australia
Offers an introduction to birdwatching.
http://www.birdobservers.org.au/

Bird Studies Canada
Canadian birding site that carries a very comprehensive selection of links to birding sites worldwide.
http://www.bsc-eoc.org/links/links.jsp

Bird Watching in Morocco
A practical guide to finding the best birdwatching sites in Morocco.
http://www.caracara.org/birding/marok00/

Birding in Canada
Canadian birding links galore.
http://www.web-nat.com/bic/

Birding.com
International birdwatching resource.
http://www.birding.com/

Birdingonthe.Net
An index to the archives of birding email lists.
http://www.birdingonthe.net/mailinglists/holzmanarchives.html

Birdingonthe.Net
Mailing lists, galleries, species worldwide and links.
http://birdingonthe.net/

BirdLinks
British birding resource that includes information about holidays and tours.
http://www.birdlinks.co.uk/

Birds Australia
Tells you everything you ever wanted to know about Australia's feathered friends.
http://www.birdsaustralia.com.au/

Birds Ireland
Tours, Irish birding, rare bird news, features, online movies, bird art, etc.
http://www.birdsireland.com/

Birds of North America
Online reference of North American birds.
http://birdsofna.org/

BirdSource
American site that encourages you to record and share your bird counts online.
http://birdsource.cornell.edu/

Birdtour Asia
Organised and tailor-made travel throughout the Asian continent.
http://www.birdtourasia.com/

BirdTours.co.uk
Hosts well over 400 reports for over 100 countries, documenting over 8,500 bird species.
http://www.birdtours.co.uk/

Birdwatching Australia
A directory of Australian birdwatching tours, bird clubs, freelance-guides, bird-orientated accommodation and reference information. The site includes a heap of international links.
http://www.ausbird.com/

Birdwatching Australia
A list of rare birds you can see, if you stay at Chambers Wildlife Rainforest Lodge in Australia.
http://www.birdwatching-australia.com/

BirdWatch Ireland
Irish birding resource.
http://www.birdwatchireland.ie/

British Ornithologist's Union
Aims to encourage the study of birds in Britain, Europe and throughout the world, in order to understand their biology and to aid their conservation. The site contains an official list of bird species spotted in the United Kingdom.
http://www.bou.org.uk/

CAMacdonals.com
Birding hotspots all over the world.
http://www.camacdonald.com/birding/birding.htm

Canada Wild Birdwatching
Wild birdwatching vacations with Canadian hosts.
http://www.canadawildbirdwatching.com/

Cheeseman's Ecology Safaris
Runs tours to places famed for their abundance of photogenic mammals and birdlife.
http://www.cheesemans.com/

Eagle-Eye Tours
Birdwatching tours worldwide.
http://www.eagle-eye.com

Field Guides
Covers birding gear, books, software, birding organizations and important travel information for birders. The company also has two decades of experience organizing birding trips to 100 destinations worldwide.
http://www.fieldguides.com/

Great Florida Birding Trail
The Great Florida Birding Trail is a collection of sites throughout Florida selected for their excellent birdwatching or bird education opportunities.
http://www.floridabirdingtrail.com/

Hotel Finca el Cerrillo
Birdwatching and walking holidays in Spain.
http://www.hotelfinca.com/

IBA
A guide to the important birding areas of Canada.
http://www.ibacanada.com/

Irish Birding
Apart from letting you know about Irish Birding Services, this web site aims to provide a mixture of news, topical articles, special features and more. There is something here for everyone.
http://www.irishbirding.com/

National Audubon Society
America's premier bird and wildlife conservation organization.
http://audubon.org/

Naturetrek
Wildlife holidays, birdwatching, botanical and natural history tours and treks.
http://www.naturetrek.co.uk/

New Zealand Birding Directory
Directory of tour operators and nature lodges in New Zealand.
http://www.birdingnz.co.nz/

New Zealand Birds
Kiwi birding resource.
http://www.nzbirds.com/

NPWRC
Bird checklists of the United States.
http://www.npwrc.usgs.gov/resource/othrdata/chekbird/chekbird.htm

Nutty Birdwatcher
Everything you ever wanted to know about the bird population of America's east coast.
http://nuthatch.birdnature.com/

Online Birding Guide to the United States
Offers a wealth of birding links that have been organized by state.
http://www.aves.net/the-owl/blnk-usa.htm

Ornitholidays
Specializes in escorted natural history and bird watching tours.
http://www.ornitholidays.co.uk/

Ornithological Society of New Zealand
Links, news, information, studies and publications.
http://osnz.org.nz/

RSPB
Charity dedicated to preserving Britain's birds.
http://www.rspb.org.uk/flash.html

Society of Canadian Ornithologists
Join online.
http://www.nmnh.si.edu/BIRDNET/SocCanOrn/

South African Birding
Regional birding sites, birding resources, the latest rare bird sightings, highlights and events, birding accommodation and tours, and more.
http://www.sabirding.co.za/

State Birds
A guide to America's official state birds.
http://www.50states.com/bird/

Traveling Birder
Birders offer other birders accommodation on a goodwill basis.
http://www.travelingbirder.com/

Wings
An Arizona based company offering birdwatching tours worldwide.
http://widdl.com/wings/contact_us.html

Wings
Another Arizona tour firm that organizes birdwatching trips to destinations worldwide.
http://widdl.com/wings/