Also try Naramig (naratriptan; has less side effects than sumatriptan, and is more powerful).
For migraine prevention, different things work for different people depending on what causes the migraine. If you know of certain foods or environmental triggers which cause the headaches, these are usually easily avoided (or at least mitigated - if you can't handle sunlight or bright light, for instance, dark glasses can help a little). Hormonal fluctuations, seratonin imbalances, etc are trickier - some preventive drugs include birth control pills (which often make the migraines worse, but sometimes control them), beta blockers (a milder herbal substitute, feverfew, is much cheaper and safer to ingest, although it takes weeks to kick in), sansert (pitzotifen), calcium blockers, Prozac (or St. John's Wort), kava kava, and valerian. Not everything will work for everybody.
The most common food triggers are aspertame, MSG, sulfites (found in cured meats, wine, and some cheeses), citrus fruits, and caffeine. Not every migraine sufferer is hypersensitive to all these substances (or even any of them) but eliminating various foods from one's diet to see which ones seem to trigger attacks, if any, is probably a good idea.
Dehydration, exhaustion, stress, oversleep, undersleep, and PMS are all know triggers. Again, if you can avoid the source of the migraine, you can exercise a little preventive medicine (often in the case of stress, this is much easier said than done).
Vampires seem to have a high incidence of migraine headaches (I suffer from them, too; so do many people on my own list). Currently, migraines are trendy enough to get actual medical research, which is a good thing as far as it goes (used to be doctors would smile and say "It's all in your head," especially if you were female, as the majority of migraine sufferers are - by a two to one margin) but you can't tell a doctor "I get migraines because I'm a vampire." I've discovered that migraines get worse if one is not feeding, or is having serious imbalance of energy (lots of pent up stress with no way of venting it...) Good preventive medicine in this case is, of course, to make sure you feed regularly. If you are a sangunarian, get blood. If you can't get blood, eat stuff that is high in pranic energy/life force: live culture yoghurt, live bean sprouts, raw tubers and vegetables, dairy products, sperm, etc. If you don't really do the blood thing, but prefer to get your life force in another manner, try to do so regularly and remember to ground and centre afterwards. I'm a blood drinker myself - I can get what I need by playing succubus, but if I can get blood I'll take it, because I happen to like blood. The important thing is to not starve yourself, in any case.
During the attack: try to put yourself in a trance. I know this is asking a lot, I often have a hard time doing it myself, but it's a good pain control technique. Count backwards and forwards from 500 until you have mesmerized yourself into a state of light hypnosis (this is much more trance-invoking than counting sheep, because it's closer to a mantra). Other methods of pain management include analyzing the pain (observe it as if from outside and describe it in detail - this often detaches you from yourself) and biofeedback (which I have never learned).