For a child under 7 years of age, you should contact the ACT Autism Advisors immediately (see http://autismaspergeract.com.au/advisors).
For an school-age or older child, the pathway is more complex. Firstly, whoever diagnosed your child should have provided some form of treatment plan. If that does not help much then you can think about:
This is the current Autism Asperger ACT website. A previous website can be found at http://autism.anu.edu.au/.
Click here for information on how to donate to Autism Asperger ACT.
Autism/ASD information booklet for the ACT ...