3 Year Old PDD/Asperger's?

I have a 3 1/2 year old son who has very odd behaviors. He rocks constantly, lines up his toys and other objects, he does not play with with any children at all, not even his sisters.  He is also extremely violent. He does make eye contact most of the time and his speech is excellent. He does not understand he, she, what, why or how and everything is I don't know. He "W" sits when he plays and he has several tactile and sensory issues such as covering ears when there are loud noises and bright lights and will only eat dry foods. I have been to every doctor known to man and cannot seem to get a diagnosis. They all say that there definitely is an issue, possibly on the spectrum, but no one will diagnose him. What can I do to get him help?

[Rebecca MacDonald, Ph.D., BCBA]

I would suggest that you go try to identify a hospital in an urban area where they specialize in diagnosis of children who present developmental delays. A comprehensive evaluation by a team of specialists will result in diagnostic information as well as treatment recommendations. You can then take these recommendations to your local school system

The most effective treatment for children with autism is early intensive behavioral intervention. This means that your son should receive 20 hours of direct teaching in language, social skills and self-help skills. Services can be provided by early intervention or the public schools in your area. You may want to look for behaviorally trained professionals to supervise a treatment program by checking www.bacb.com for a person in your area.

[Sally44]

You need to go to your doctor and ask for a referal to professionals that are experienced in diagnosing autism spectrum disorders including Aspergers.
The first professional to assess a child is usually the Speech and Language Therapist.  Your child does sound like they are having problems with language development.
He also sounds like he has sensory issues which maybe Sensory Integration Disorder.  This can affect any or all of the senses eg. vision, sound, touch, taste, smell, balance and co-ordination.  This maybe responsible for the difficulties you have mentioned of rocking constantly, tactile and auditory issues (covering his ears), bright lights, only eat dry foods etc etc.  
As he has these sensory difficulties it might also be worth googling Irlen Syndrome and seeing if that is relevant to your son.  It can be helped enormously just by wearing tinted lenses in glasses.  It is a recognised condition that affects a considerable amount of autistic and dyslexic children/adults.
An Occupational Therapist should assess for sensory difficulties and they should have experience of SID as well as autistim.  Your doctor should refer you to an OT.
Your child will also usually be seen by a clinical paediatrician and clinical psychologist.
You might also want to google Carl Delacato and Olga Bogdashina for more information about sensory differences and how they affect behaviour and perception.
Is his violence around changes in routines or expectations or with being expected to take turns or share things.  What is he like with transitions ie. having to turn off the TV or computer or being asked to do something.
You can also google DSM IV (this is the diagnostic criteria for autism/aspergers).  Look at the criteria for autism and aspergers, make notes about how it seems relevant to your son (do the same for Sensory Integratiion Disorder) and go and see your doctor again.

[Meredith300]

He does freak out if there is any change in routine or if we take a different route home. We have not found any reason for the violence. Nothing seems to trigger it. Another child might be playing and he will walk up and hit them for no reason. The School Board has started the process for OT and Speech, but that will take months. In the mean time we are helpless.

[Sally44]

You don't say what country you are in, but here are some suggestions you can try.  Joining a parent support group in your area will give you alot of advice and support because they will have gone through what you are going through now.  It will give your family a chance to meet other families with children similar to your son.  In these groups their behaviour is understood by everyone and not judged.  In my area we hold a twice weekly group which we would in the gym of the local community college.  The children pay a fee to get in and they can also have siblings and friends along too.  They put out all the gym equipment, including a trampoline and bouncy castle and spend 2 hours letting off steam and playing together.  There are supervisors watching the children.  The parents go into the school staff room and have tea/biscuits etc.  It is a chance to chat and swop information.  Some parents take in laptops and get some work done!  It is just 2 hours off with other people in a similar situation.
As your son has sensory differences I would recommend buying a book by Olga Bogdashina called Sensory and Perceptual Differences in Autism and Aspergers.  There is a caregivers questionnaire at the back of this book which you can complete to get a sensory profile of your child.  You can complete that and give it to the OT when you see them.  This questionnaire is used by our autism outreach department, so I know it is reputable.
If the wait for OT is long (it took us 2 years!), then you can pay for a private OT to come and give you a programme to be getting on with.  If you decide to do this make sure you get one with experience of sensory integration as well as autism.
You say his speech is excellent.  But is he repeating words/phrases he has heard you say or has heard on TV/DVD/Films?
Do you think he understands what you say?
Does he ever give an unrelated answer to a question you ask him.
If it does turn out that he doesn't have any language difficulties (which will be unusual), it is still the speech and language therapists area to work on his social interaction and play skills.  He will need to be explicitly taught all these things.  
For example, my son wants to play and interact, but doesn't know how to do it (he is 7), so the SALT is going to start teaching him some phrases to say in certain situations to help get him started.  When he learns these phrases he can rely on them to get him going eg. 'what is your favourite TV programme'.  If he can ask a child that, that is a way of getting into a conversation.  But he has to learn these things, they will not come naturally.
Remember you are not helpless.  You are the ONLY people who will advocate for your child.  Make sure you always put things in writing (even if you have spoken on the phone follow it up with a letter).  Find out what your son's educational rights are and keep pushing until it happens.  Please don't wait for professionals to 'do the right thing'.  I know this sounds very cynical, but the fact is that everything runs on a budget and it is not in their interest to provide for all of your son's needs.  But there are laws, and when you find out what they should be doing and point it out to them, they have to respond.  Don't be afraid of getting private reports if you think it would help.  Make sure they are professionals that are independent (ie. not working for the State or Health Service) and that they are used to providing reports for Educational Courts.  I am going through this process in the UK and have just managed to get the Education Authority to agree to my son having speech and language therapy sessions from a therapist once a week and daily sessions with a teaching assistant.  No other child in his school gets that level of support.  But the private report I paid for proved that he needed that level of therapy.  I know we shouldn't have to do any of this.  Having a child on the spectrum is enough work!  But remember his future is in your hands.  Don't be afraid or feel guilty, just find out what you can do.  It has taken me years (from age 3 to 7) to get to the stage I am at now.  I am finally happy with his school and the support he will be getting.
As he is at nursery age, have a look round at nurserys and schools that have experience of teaching children on the autistic spectrum.  I cannot emphasis how important it is for the school to know how to support him and what strategies to use to help him learn.  Places in these schools are usually limited, but you may be able to get him a place just as a mainstream pupil. But I'm talking about in the UK, so things might be completely different where you are.
The more you find out about autism/aspergers the more you will understand your child and how it affects him.  Every child is different.