A lot of people do have success with melatonin. I also find exercising during the day at some point, not eating late and having a relaxing night time routine helps.
I AM LOOKING FOR THE SAME THING . . . TEAS SUCH AS CHAMOMILE AND MELATONIN HELP BUT I AM STILL LOOKING . . .
The gold standard are CBT sleep training programs for adults. These are completely substance free and represent a permanent solution. Much good info online if you're the self-help type. If not, see a counselor or sleep doc that uses it.