I've taken both melatonin and valerian, and they worked for me, but I've found something even better, and I buy it at Walmart. It's called Alteril (somnia latoril) - All Natural Sleep Aid, Maximum Strength. It has both Valerian and Melatonin and a few other herbs that are good for you.
http://www.alteril.com/
if you go to the tab "Get it today" it will list all the stores that it is available at.
I've taken Ambien, Lunesta and never seem to keep me asleep all night long, still wokeup exhausted. Special note about Melatonin, you should only take 3 days in a row and then take a break.
This stuff Alteril, you can take either one or two, depending how tired you are. I usual take one during the week, then sometimes I will do 2 on the weekend. I even gone without it, and slept all night. I've stuggled for 8+ years with trouble sleeping.
Hope you try this out. You deserve a good nights sleep.