Autism Homepage
The above is training in Wisconsin. Even if you are not a schoolteacher I bet you could get in on this. Haven't researched it myself, but do understand where you are coming from on getting certs.
I was a licensed caregiver for a 14 yr. old severely autistic non verbal boy and it was very rewarding. He improved so much - did you know some people can actually no longer be considered autistic? It takes time and patience but it does work. My 16 yr. old nephew is proof.
Write any time if you have questions on handling autism.