I swear by 5HTP. It is a cheaper & safer alternative to tryptophan -If I remember correctly it is a precursor to meletonin. Be careful with supplements that effect your serotonin levels if you are on any SSRIs or certain other drugs - certain herbs like skullcaps, Valarian, Kava Kava have Anxiolic properties (wikipedia). Check with your doctor!!! Bu not all doctors will give you any alt medicine advice.
The Food Bible suggests taking Hops, Passion Flower, Skullcaps, 5htp, Californian Poppy and Lime Flower.
I also take Holy Basil, Rainbow Light's Cal-Mag (Magnesium relaxes you, as does Niacin and other B vitamins) and a good Omega complex from Nordic Naturals.