NancyCk, check in your area for Mental Health ('Counseling & Guidance') Facilities that accept low-or-no income patients. If you make an appointment with a Counselor or Therapist for help with your anxiety and depression, you can explain to them why you think you may have AS and would like to be diagnosed - they, in turn, can refer you to a licensed Psychologist for testing.
Your cost for this will depend on your income and access to insurance, etc. It may be little or it may be nothing. If you are formally diagnosed, you can then apply for Disability - I recommend going through an attorney who specializes in SSDI cases (you'll find them advertising all over television, no-win, no-fee).
For me, the hardest part was trying to explain on paper, to the Social Security drones, exactly how my AS constituted a debilitating handicap - at the time, I was still learning about it and coming to grips with its effects myself, and I absolutely despise filling out paperwork and answering what I feel are intrusive (and often irrelevant) questions.
Coming to understand the impairment of Executive Function in the Autistic brain finally helped me get a handle on how to explain it in a way a bureaucrat could understand. Of course, I think the reports my Therapist was filing went a long way, too.
Good Luck!
PS: Also see Sati's current thread in General Autism Discussion entitled "Cheap DX in Pittsburgh, PA" - it's only about 130 miles from where you are, give or take. Could be a simple solution for you.