When beginning your research, reference materials (encyclopedias, dictionaries, bibliographies, etc. . .) can be a great way to get started. These resources offer overviews of thousands of topics and will help you launch into your search for the scholarly resources that you will need to use to support your research.
When brainstorming, it can also be helpful to browse popular, non-scholarly resources in order to understand the status of general discourse on your topic and explore diverse viewpoints while developing thesis statement that can be supported with scholarly resources.