Search the health section of the library (610-617) or these collections that are on the reserve cart:
National Institute of Mental Health http://www.nimh.nih.gov
National Institutes of Health http://www.nih.gov
Databases are collections of vetted and reliable resources. Databases are especially helpful in more academic research.
Find out if there's a nonprofit group that raises awareness about your topic (ex. Alzheimer's Association). These groups often have good resources written for the general public. To find them, try adding site:.org to your Google search to see only .org websites.