6 yr old can't get to sleep

[wotsit1999]

I am going to post this on a few boards for maximum coverage! My son turned 6 last week and for about 2 years now he takes hours to get to sleep. He does not get out of bed, he just lies there/rolls around and hats to himself for hours. I put him down at 8, he will drop off around 11. He is exhausted at school. I have tried everything I can think of, but please suggest anything I haven't!! So far tried:
Tiring him out
Changing his diet/less sugar
Baths/lavender
Warm milk
No TV
Bedtime story
Good routine
CDs with stories
Black out curtains
Kids hypnosis CD
Is there anything I am missing? I really do not know what to do anymore.

Chamomile tea helped DD and so did melatonin. You need a script for melatonin in the UK.

I've heard about melatonin from doing some research on google, I wonder how likely it is the GP will prescribe that for us. Great idea about the Chamomile, thank you!

Bach sleep remedy? Doesn't work for me but does for a colleague.

Have you asked for a referral to a sleep clinic?