Some case studies can be found in article databases such as EBSCO's Business Source Complete though most Harvard cases will not be available full-text. In addition, many schools sell cases for a small fee or provide some cases for free. You can either visit their individual websites (Darden, Harvard, INSEAD, Ivey, Kellogg, Sloan, and Stanford) or use an aggregator, such as The Case Centre, to search and purchase a case study. At present, the library does not purchase cases used in Cornell classes as these are almost always part of the required class course pack.