well i don't have insomnia, but some things that help me out are opening my bedroom window, and putting on some soft music.
the sounds outside, (or at least the sounds where i live), tend to calm me down and help me sleep. the music i listen to is from video games, specifically minecraft and skyrim. that music tends to keep me calm as well, and with the noises of nature outside, it makes sleeping pretty easy.
is it just not being tired that you won't go to sleep? or is it that you're stressed out?