So: when preparing to do research, you must ask yourself
What different kinds of information sources do I need to locate?
Do I have special concerns regarding the currency, comprehensiveness and/or authority of the information?
What tools should I use to find those different sources?
use the online catalog to find books
use periodical indexes to find articles in journals, magazines and newspapers
use web search tools to find websites
This way, you'll be looking in the right place for the right thing, and your chances of finding what you need will improve dramatically!