Your state department of agriculture provides a State Veterinarian and laboratory testing services to monitor poultry populations (including backyard flocks) for serious outbreaks of disease. They also provide information and education about avian health, disease prevention, and advice on bio-security measures you can take to protect your birds. When you are confronted with a death or disease in your flock and you do not have access to a private avian veterinary (due to availability or inability to pay), you should feel free to turn to your State Veterinary through your state dept. of ag. Here is a listing of those professionals, by state, as of 2010: (Perhaps you'd like to bookmark for future reference)
http://www.usaha.org/StateAnimalHealthOfficials.pdf
http://www.usaha.org/StateAnimalHealthOfficials.pdf
