Linda Lou,
Sleep is sacred &so precious.
Lacking sleep can do horrible things to you, <img src="/ubbthreads/images/graemlins/reallymad.gif" alt="" /> <img src="/ubbthreads/images/graemlins/dead.gif" alt="" /> <img src="/ubbthreads/images/graemlins/looney.gif" alt="" /> <img src="/ubbthreads/images/graemlins/homer.png" alt="" /> <img src="/ubbthreads/images/graemlins/flu.gif" alt="" /> <img src="/ubbthreads/images/graemlins/blah.gif" alt="" /> <img src="/ubbthreads/images/graemlins/coffee.gif" alt="" /> <img src="/ubbthreads/images/graemlins/help.gif" alt="" /> <img src="/ubbthreads/images/graemlins/skullbones.gif" alt="" /> <img src="/ubbthreads/images/graemlins/nausea.gif" alt="" /> <img src="/ubbthreads/images/graemlins/hangingonanlimb.gif" alt="" />I've been there.
Here are some suggestions that helped me;
(You have probably heard all this before but here goes)

Pumpkin seeds,
Camomile tea,
dim the lights coming up to bedtime,
hot bath,with a few drops lavender oil &maybe some camomile in the bath water.&drink the tea too.
No tv or computer for at least 2 hours before bed?
If you have caffeine/stimulants have them as early as possible in the day as they stay in your system for at least 6 hours.
I used to supplement magnesium before bedtime,this helped alot.
Any time I set out to meditate I nod off!
Reading a maths book or something you don't find personally interesting
These might help you sleep. <img src="/ubbthreads/images/graemlins/zzz.gif" alt="" />

ps I had ahuge sleeping problem,I was breastfeeding for 10 months,my baby wanted to feed or comfort or something every 3 hours,even when he was weaned it took year or so for me to be able to unwind enough to sleep through a night,I was seriously sleep deprived
"Deep sleprivation" is what I call it,anyone been there will understand.
It can become a vicsious cycle where you wake up &become annoyed at waking up,saying to yourself things like"oh great ,now I'm never going to get back to sleep,I'm going to be tired tomorrow,etc etc.These thoughts(for me anyway)sent all kinds of responses through my body like wake up!emergency!the last thing I needed to get back asleep!
When I was aware of this thought process,I was more able to control it &get calm enough to go back to sleep.