residential / supported living for young adult

Hi @cathymee, and welcome to the community. Very glad to have you with us.
I'm only really here to say hello and let you know your post has arrived safe and sound, as I don't have the information that you need. There is every chance that others here at Scope will be able to help and will get back to you.
I have tried a quick search and not really come up with anything, but that could be down to my search terms or to the search engine itself, so bear with us, and don't hesitate to be in touch again if you don't hear fairly soon.
Only as a thought, I'm wondering if you've tried the National Autism Society, NAS, at http://www.autism.org.uk/
Anyway, please stay in touch, and don't hesitate to tell us more about yourself and your son. You are very much among friends here.
Warmest best wishes to you both,
Richard