Melatonin did not help me with my sleep either. I am definately not the poster child for good sleeping, I am having terrible issues.
But sometimes I find that Celestial Seasonings Sleepytime Extra Tea with Valerian is helpful for relaxing and getting to sleep. You can find it in the grocery store.
Also, kava-kava tea is supposed to be helpful for sleeping and depression. I found it at an herbal-remedies, incense-type of store.
I'm not sure if it's the ingredients or just the time I take to make tea, sit down and drink to relax that can help. It doesn't help all the time, but it sure doesn't hurt.

It sounds like your nutritionist is out to make a buck.