Reference books, such as dictionaries and encyclopedias, are great tools for learning about a topic. The background information and summaries they provide will prepare you to better engage with meatier resources such as books and journal articles. Below are a few reference items to help you get started.
Search the library's catalogue for print and ebooks.
When consulting books for your Annotated Bibliography, consider the question of authority: who is the author, what are his/her credentials and affiliations? Who is the publisher of the book?
Remember that authority is in many ways constructed and contextual. For example, Bart D. Ehrman, James A. Gray Distinguished Professor of Religious Studies at the University of North Carolina, is a New York Times best-selling author and according to his Wikipedia entry, "one of North America's leading scholars in his field." His credentials would seem to make him an authority. Yet the fact that he denies the resurrection should make us consider the idea of authority with a healthy skepticism. Be open yet critical and discerning.
The reader of your annotated bibliography will also be interested in the accuracy of a particular book. What claims is the author making, and do these find support in the text itself? Does the author interact with other scholars and sources? Are there any factual errors that could call into question the reliability of the scholarship?
Two criteria you will want to think about when preparing your Annotated Bibliography are currency and authority. All of the databases above will allow you to refine your search results by publication date, and most will allow you to limit your results to include only peer-reviewed articles. Peer-reviewed journal articles have been evaluated for scholarly quality by an independent expert in the same field prior to being accepted for publication. This screening process ensures that the article meets the standards of their discipline, yet in no way does it guarantee the absence of bias or the fair representation of various perspectives.