Have you seen a neurologist? One that specializes in migraines can be your best resource.

Otherwise, I recommend the book "Heal Your Headache." My neuro gave it to me, and by following the plan --which is hard and extreme at first-- I nearly eliminated my need for medication. You have to follow it, though; going halfway won't work.

And, really, you should consult a neuro before starting anything you read in a book!