The Law Library maintains a database of previous exams and essay questions for many classes and instructors. You can access it from on-campus (or by using VPN from off-campus) by clicking this link on the main Law Library web page: Exam File
The Library also maintains a collection of study guides, study aids and review materials on a book case outside the 1st floor restrooms. These items do not need to be checked out and are on a take-one-leave-one system.
There is also databases containing study aids like nutshells from Wolters Kluwer and West, as well as subject research guides compiled by the Law Library Reference Librarians.