Heath,
Try Levonian's suggestion. Barring that, I don't know of any thing that might work, unless you go the prescription route.
I also suffer from PTSD with wicked sleep issues. Unlike you, I had to resort to prescription medications to deal with this.
I'm currently taking phenergan for sleeping. It's a prescription antihistamine. It's prescribed for people who suffer allergies. It's also commonly prescribed for post surgical nausea, and to combat post chemo nausea. It WILL knock you on your backside! That's what I like about it!
I absolutely refused to take anything that was addictive, so that's why I'm on this. The common treatment for insomnia is the benzodiazipine tranquilizers (xanax, valium, ect), and I won't go there!
Incidently,
Tyenol PM, Advil PM, and Sominex are common OTC sleep aids. They all contain benadryl, which I've tried. Worked for a time, but didn't work long term.
I've also tried Kava Kava, which worked real well, but again, wasn't a long term solution. Kava is considered the "natural" xanax.
Whatever method you choose, I wish you luck. PTSD really bites, man! I've been there, and I'm currently still there.