I don't know if this works at night, but I tried it once when I needed to take a nap during the day (don't normally, but I needed rest for that night). Anyway, I had just read that Napoleon used to have a trick for falling asleep.

It is said he would picture a large dresser (dresser of drawers with lots of drawers). He would then think about the problems plaguing him, and he'd picture opening the bottom drawer and placing his biggest problem in it. He'd close the drawer and repeat the process, working up the dresser, placing problems in one drawer after another. And from what I read he claimed he had never reached the top of the dresser.

Makes sense when you think about it, as the problems get smaller and smaller on your way up, until you're not even dealing with real problems anymore, just trivial things that can't keep you awake.

It worked for me the day I needed to take a nap.

Also, if noises keep you awake, run a small fan near your bed. White noise covers other sounds and is soothing.

Avoid bright lights after sundown (artificial light throws off your body's clock).