Before you can decide where to search you need to identify the type of information and sources you need:
News - From newspapers reporting daily events (New York Times)
Magazine - Often called "popular" articles, these are general or for a specific interest (Time, Discover)
Trade - By and for specific industries (Advertising Age)
Scholarly - Reporting research, written by and for scholars and researchers (American Journal of Psychology)
For in-depth coverage and longitudinal research - Look for books in the library's General Collection and eBook Collections
For background information - Look for Reference books
Once you've identified what you need, you can look for the databases that cover your topic with the type of sources that you are looking for. Some databases contain only articles while another might contain a wide variety of source types.