The first step in creating a literature review is, of course, finding the literature to review. A good literature review should be as comprehensive as necessary to identify all of the major works and debates on your research subject. Here are some tips for going beyond basic keyword searching in order to find as many sources as you can.
Use these links to identify a database that's relevant to your research question.
So you have an article in your hands, and you've already raided the bibliography for citations. But these are all older sources the author used. How do you know who cited this article? Try one of the following search tools to find "future" sources that cite the article you already have.