Melatonin always worked wonders for me. It never made me sleepy, but it allowed me to go to sleep when I wanted to. I would go to sleep everynight around 10pm, and then wake up at 6am feeling completely rested. The only problem is that, according to some studies, long-term use of melatonin supplements can cause a hormonal imbalance, which is why I stopped using it. Also, as an added perk, melatonin supplements are awesome for lucid dreaming.
Also, diphenhydramine is good too, but it makes me feel groggy the next morning, and alcohol makes for some restless sleep, in my experience.
I tried Sominex (promethazine) I rarely take any sleep aid or any medication at all - not even aspirin. (I can count on two hands how many times in the last decade) So it might have been me being paranoid, but Sominex made me feel as if I wasn't going to wake up in the morning. I could feel it working, and I kept dozing off but had a bit of a panic attack and would wake up again. I did have more sleep - but my brain felt like it had been doused in chemicals. I would take it again if I really felt I needed it - but It's not the most natural of sleeping aids - I don't think there are many anyway. It's better than no sleep, I guess : /