Reference books are good places to begin your research because they include criticism of many different authors and literary works. They often also include author biographies. Remember: these books may only have excerpts of critical essays, not complete essays. Learn to search for complete essays under the Finding Articles tab.
Literature and literary criticism books are shelved in the P-PS call number areas. Print reference books are located behind the Research Assistance desk in the tall book stacks and are library use only -- you can't check them out, but you can photocopy/scan pages from them.