Have you heard of any classes on 504 Plans in the Solano, Sacramento county areas so that parents can understand their children's rights?
Your best bet is to contact the national office of Children and Adults with Attention Deficit Disorders
(CHADD) at 1-800-233-4050 to see if there is a branch of this group in your area. They should know about parent meetings where you can get some additional information about Section 504 guidelines.
You might also want to read Harvey Parker's Problem Solver Guide for Students with ADHD. He has a good chapter about modifications and accommodations that you might request for your child under Section 504.