I've lived in NY and NJ. So far the best and safest place for children on the spectrum would be NJ. There are so many services offered. I live in the "hood" and Jeremy goes to one of the best schools in the state, it was No.3 last year. But remember where ever you go you have the last say in their education and services.

i live in Pennsylvania and with a diagnosis, you qualify for medicaid regardless of income or other insurance coverage.

California does have great state benefits for ASD, but like most states you have to know you rights and what to ask for. California has very good laws of mandated coverage for insurance companies as well.
With Obamacare your children have guaranteed availability right now (since 2012). You can put your kids on a child only plan. No insurance company is allowed to deny your kids coverage.
When 2014 hits you too can get insurance regardless of preexisting condition. You may even qualify for a subsidy depending on your income.
Reason I know this is that I work for an insurance company.
There are a lot of support groups out here. Many organizations devoted to helping our kids and providing services.
Regardless of where you choose, look at the state laws regarding autism and insurance coverage. Maybe looking at Autism Votes website may help you know where laws have been passed requiring insurance coverage for ASD.
Hope this helps

Welcome to NJ - I hope. Our state has wonderful services, Has state insured services, and mandated most appropriate schooling. If you do move here, I can give you tips on where to move for the best services for your chidren

we live in southeastern PA and have great services. Many great hospital programs and treatment centers, plus my son's public school is very good working with us. They are actually the ones that administered the ADOS and diagnosed him which helped with getting his IEP set up quickly. They also assigned a mobile therapist to come to our house once a week to work with my son on getting up in the morning and to school on time and not missing school days. Since they assigned the therapist, the school district covered 100% of the cost. The school was also who informed me that my son qualified for medicaid, helped me complete the application and hand delivered it for me to be sure it got processed. My son feels safe and cared for, the office staff greets him by name each morning and that makes him feel special and reduces the anxiety. I feel very fortunate to live where we do. If you're considering this area, look into services at Children's Hospital of Philadephia, AI DuPont Children's Hospital (in Delaware but just across the state line from PA) and Devereux. All excellent facilities. Lots of support groups, special camps, free activities through the treatment centers and even social events specifically for ASD kids (movie theaters have special days where the volume is lower and lights are left on, arts & crafts, theater groups, etc all for ASD kids.)