Post Traumatic Stress Disorder:
Highly Credible=
http://www.jstor.org/stable/3058795?seq=1&Search=yes&term=system&term=limbic&term=PTSD&list=hide&searchUri=%2Faction%2FdoBasicSearch%3FQuery%3Dlimbic%2Bsystem%2BPTSD%26gw%3Djtx%26prq%3Dlimbic%2Bsystem%26Search%3DSearch%26hp%3D25%26wc%3Don&item=1&ttl=10&returnArticleService=showArticle&resultsServiceName=doBasicResultsFromArticle&cookieSet=1
annoying long link to JSTOR which is a highly credited medical research type site. They search medical journals and everything that you find is published and nearly all of it is peer reviewed
Okay=http://cybersarges.tripod.com/ptsdhistory.html This is a credited site hosted by an American veteran of the Vietnamhttp://en.wikipedia.org/wiki/Post_traumatic_stress_disorder war. His site is obviously biased on anything involved in the military, but the facts you can find in the medical information is general and reliable.
Bad=http://en.wikipedia.org/wiki/Post_traumatic_stress_disorder
wikipedia good for boredom and providing heuristics but nothing practical.