I tried amitryptaline briefly after being prescribed it for sleep, I was taking 10mg but it did nothing to make me sleep, although I wasn't on it very long because it made me feel rough the next day - gave me a real thick head. I learnt it's an old drug from the 60's designed for depression but appears to be prescribed for all sorts of things.

l-theanine is in green tea so you don't need to buy special pills or anything, just make a brew!