I’m probably much to late to help you out now, but for future reference, perhaps:
Computer/Television screens tend to throw off your circadian rhythm, so if you have trouble getting to sleep you should try to avoid as much late night computing and TV watching as possible.
Try not to ever do anything in your bed except sleep. (And maybe sex). If you save your bed for just sleep, your body will naturally feel like it SHOULD be asleep when you’re in bed. That will help, whether you’re actually tired or not.
I, personally, tend to read anywhere from 15–45 minutes before I actually go to sleep. My biggest problem is usually that I have too much going on in my mind, so having something specific to focus on helps.
I’ve heard that if you tend to think about all the stuff you need to do the following day, you should keep a notepad and pen by your bed and write down all the stuff you need to remember before trying to sleep.
One of the worst things to do when you need to sleep is get on the internet, or even just your computer in general.