Trap–Neuter–Return is the only population control method proven to reduce feral cat populations both immediately and in the long-term.
TNR is safe, cost-effective and strongly supported by the public. If it is
the concern of the larger community to safeguard native wildlife from
the predations of feral cats, TNR is the best way to achieve that goal.
Numerous studies published in the Journal of the American Veterinary Medical Association (JAVMA) back up these facts. In contrast, other jurisdictions that for decades have practiced trap-and-remove (kill)
policies for feral cats find that, despite increasing amounts of money
and manpower, there are more feral cats than ever.

Making a Difference: Laura Comyns and the Kitty Committee An interview with Linda Alexander, February 2007.

National

Alley Cat Allies Leading national advocacy organization dedicated to the protection and humane treatment of cats; many resources.
Friends of Animals Founded in NY in 1957; all types of animals.
The Animal Rescue Site Click free daily to give food and care; shop there too!

Regional

Forgotten Felines Sonoma County's largest group dedicated to TNR, adoption and colony care. Lots of information on trapping and socializing feral cats.
WeCare Animal Rescue Uniquely special no kill refuge for cats and dogs located in St. Helena, Napa County, Northern California. Adoptions; feral and special needs facilities.
BrightHaven An animal place of love, learning, hospice and education, in a beautiful Sonoma County garden setting.
FAIRE Friends of the Animals in the Redwood Empire, Sonoma County; provides spay/neuter vouchers which Kitty Committee administers.
Sonoma County Wildlife Rescue
Humane Society of Sonoma County
Sonoma County Animal Shelter

Diet Sources

Primal Pet Foods High quality raw frozen food; Bay Area-based (San Mateo).
Feed This, Inc! " 'Cause dogs can't cook & cats won't!" Healthy raw food following Kymythy Schultze's The Ultimate Diet; Forestville, Sonoma County.