Use RefWorks to keep track of all your citations, then easily create bibliographies. Most databases let you add articles and books to your RefWorks account with just a few clicks!
See Puget Sound's detailed RefWorks Guide
It's up to you to make sure that the RefWorks output matches the latest requirements of the style, and that no data is missing.
Which citation style you utilize depends on the discipline of the course you're taking, and the citation style chosen by the department or professor.
Collins Library has also developed helpful citation handouts:
Chicago Style: Notes & Bibliography System (Humanities Style)
Additionally, there are many great online sites that will assist you in interpreting and utilizing the various citation styles. Here are two good ones to be aware of.