Nancy can probably give you lots of great links as she is the links master, but do know this is a common problem... for migraine and insomnia to go together and form a problematic cycle. Have you spoken with your doctor about the insomnia specifically? My neurologist is a big advocate for good sleep, as she explains that during the deep phases of sleep your brain makes certain chemicals that help suppress migraine.
I was on one preventative for a while that had natural side effect of sedation, but had to go off it for other reasons. As soon as I came off it, my insomnia flared up again, and I was once again having daily migraines, my neuro put me on a different med, which in low doses can be prescribed for insomnia, and isn't habit-forming. I was really glad I made that extra trip to the doctor because like you, I had exhausted all the at-home remedies... exercise, dark room, cold temperature, winding down, warm bath, you name it. I just needed my meds adjusted correctly. So my advice is to talk to your doctor.