Review various scholarly and trade published literature on your topic and create your annotated bibliography.
Use search engines such as “Google” or other search tools such as “ERIC” as a starting point.
Pay attention to domain name extensions, e.g., .edu (educational institution), .gov (government), or .org (non-profit organization). These sites represent institutions and tend to be more reliable but be mindful of possible political bias in some government sites. Be selective of .com (commercial) sites. Many .com sites are excellent; however, a large number of them contain advertisements for products and nothing else. Learning how to evaluate websites critically and to search effectively on the Internet can help you eliminate irrelevant sites and save time. Avoid using Wikipedia. It provides user driven content with typically limited credible resources.
Go to your local library to review books and other related resources such as:
Law enforcement and tactical operations books
Encyclopedias and dictionaries
Government publications, guides, & reports
Trade magazines & newspapers
Businesses and government agencies, or contact knowledgeable people in your community.