Case studies from the Harvard Business School Press can be purchased from the publisher's webpage http://hbr.org/search//4294958507/
Each monthly issue of the Harvard Business Revview includes one case study. You can locate these through the Business Search Premier database by searching for Harvard Business Review and limiting your search to case study as a document type.
There are other case studies in both the ABI and Business Source Premier database. These examples of case studies illustrate a variety of ways to analyze a case and could help you think about your own assignment.
For example. the ABI database includes full-text of Journal of the International Academy of Case Studies from 2004 to the present and the Journal of Business Case Studies from 2009 to the present.
Your professor may provide you with a series of guiding questions for a case analysis. Your textbook publisher may provide suggestions for case analysis. Check in your textbook and in any supplmentary materials information on case analysis.
Case studies require you to apply your knowledge and experience to a real business problem. Your textbook may recommend some articles for you to read to guide your analysis.