Want to find out if the Fall migration has started. Have a photo of a bird you can't identify? Want to talk to other birders? Here are email lists, as well as birding groups, so you can find others who share your interests, have great birding pointers, and who can tell you exactly what that "mystery bird" is.
There are a number of maiing lists available to the interested birder, covering the San Francisco Bay Area and beyond.
South Bay Birds: Birding specifically for Santa Clara county
Peninsula Birding: Birds and Birding in San Mateo county.
SFBirds: Birding in the city of San Francisco
North Bay Birds: Birds in Marin, Sonoma, and Napa counties
East Bay Sighting: Birds in Alameda and Contra Costa counties
Central Valley Birds: This covers a larger area, including San Joaquin, Stanislaus, Yolo counties
Sacramento Birds: Birding in Sacramento county.
STA_birds: Birding and sightings specific to Stanislaus county.
Central Sierra Birds: This list covers all of Alpine, Calaveras, Mariposa, and Tuolumne Counties. This region includes the Stanislaus National Forest and Yosemite National Park
NW CalBird: Birding in Humboldt, Del Norte and Trinity counties
Northern California Birdbox: This is an announcement list aggregated from sightings,a nd is sponsored by the Golden Gate Audubon society. It covers and aea bounded by Monterey through Mendocino counties.
Interested in sampling the mailing lists? sialia.com keeps a current activity list from California birding mailing lists.
Napa and Solano Audubon in the North Bay counties
Golden Gate Audubon in San Francisco
Sequoia Audubon in San Mateo county
Santa Clara Valley Audubon Society
Ohlone Audubon Society in Southern and Eastern Alameda County
Mt Diablo Audubon Society Contra Costa and northern Alameda county.
South Bay Birders Unlimited Santa Clara county
Santa Cruz Bird Club Santa Cruz County