In addition to scholarly articles and books on your topic, here are some resources you should consult when seeking criticism of an author or work:
Literature Criticism Online
Find reviews and criticism of an author's works, including reviews by contemporaries of much older works in full text. The index can be confusing - ask at the Research Help Desk if you have trouble with it.
Biography Resource Center
Along with narrative biographies, you will find references to reviews and criticism in scholarly and popular publications. Many biographies also include a complete list of the author's works, and help to put those works in context within the author's life.