First Signs (identifying early signs of autism spectrum disorders):

CDC Act Early for Autism:

Autism Consortium (has many resources for autism spectrum disorders; click "resource database" to search for providers/therapies by area of MA)

Federation for Children with Special Needs (based in Boston):

A Parent's Guide to Special Education (a very helpful resource for special education and IEP planning):

Nonverbal Learning Disorder:

Attention Deficit/Hyperactivity Disorder (ADHD):

Learning Disabilities