To research issues in psychology, such as a specific disorder, there are several key resources to explore.
Articles & Dissertations? For scholarly articles, book chapters and dissertations, search:
PsycInfo. This is the core index to articles in psychology. If you only use one psychology database -- this would be the one! Articles, like books, will likely address treatment, intervention, and prevention issues. PsycInfo is now on the ProQuest platform.
PILOTS will provide articles on post-traumatic stress disorders.
PubMed is the best source for articles related to medicine, pharmacology, psychiatry and psychology.
MIT Cognet. The CogNet Library, focused on cognition and brain science, provides a searchable collection of digitized handbooks, encyclopedias, textbooks, journals and ebooks, along with an archive of materials from brain science conferences. Texts are provided by The MIT Press and other publishers, professional associations, institutions, and individuals who are willing to publicly share access to online works. CogNet is a self-contained full-text database.
Academic Search Complete for articles on multi-disciplinary topics including psychology.
Web of Science for articles on social sciences and psychology. Includes the Science and Social Sciences Citation Index. These let you find "forward citations" -- update your research by finding articles that cite an article.
Digital Dissertations. Search dissertations on all topics. Access to dissertations submitted by UC Ph.D. candidates as well as candidates at most other American universities. Full-text available.