K2:
As Jim said, this section is full of all sorts of help. Have you seen a headache specialist or pain doctor yet? I would highly recommend seeing one as your next step, if you haven't seen one already. I would go into any appointment armed with a copy of the ANA booklet on headaches, and the article on headaches from a recent newsletter (I can't remember which one exactly), which excerpts information from the latest ANA symposium on headaches. Most doctors aren't familiar with the kind of head pain that most of us suffer from and these publications can be useful to them.
Most of us have tried singly or together, several of the therapies you have already tried. Each person responds differently, and it may take you some time to find something (or a couple of things) that help you.
I also want to tell you that the headaches do change over time. They decrease in intensity and frequency. I am six and a half years out from my surgery, and although I still suffer from headaches, they are not as bad as they used to be.
Hang in there. Be persistent. There is relief to be found and a host of folks on this forum to offer support.
staypoz