Library catalogs and index databases include much of the information you need for your reference list. Sometimes there are elements missing which you will need to add once you get a copy of the actual book or article. For example, some databases do not include the author or title of articles from newspapers. When you look the actual newspaper up, it will give you those pieces of information.
In addition, entries in catalogs and databases are not formatted to match the guidelines in any of the style manuals commonly used in academic research. You will need to take the database entry and edit it to follow the style manual you are using. For examples, see How to Read a Citation available on Passports.