You will find most subject specific books and other resources by doing a catalog search in the library. You will also discover certain indispensable tools unique to each subject area. A good example is a huge collection of research tools published by Gale Research Company:
Contemporary Literary Criticism (CLC)
Twentieth Century Literary Criticism (TCLC)
Nineteenth Century Literary Criticism (NCLC)
Classical and Medieval Literary Criticism
Each of these is a multivolume set. They are collections--copies really--of critics' essays and other writings about literary works. Criticisms can be looked up by critic, author, or title.
Go to your library and have the librarian show you how they work. Also, there may be other sets at your library by Gale. There is an excellent one on Shakespeare, for instance.
Please send comments to: Colby Glass, MLIS