Have you given the a written request for those specific evaluations? They have to respond, by law. Writeslaw.com has more info on how to write the letter.
Honestly, though, your best best is probably going to be to have him evaluated by a private doctor (developmental pediatrician or neuropsychologist) and then bring the results to the school. That's what we did. The school also did their own assessment, but knowing we had a full report from a neuropsych I think helped them just accept that they couldn't really fight us on his diagnosis (PDD-NOS), and in our state (TX) a diagnosis on the spectrum pretty much equals an automatic IEP, regardless of grades.
