The library has a rich collection of children's and young adult literature. You can find both fiction and non-fiction titles by browsing the Children's Literature Collection on the third floor of the Main Library or by visiting the Worlds of Words collection in the Education Building. Once you've picked your author, you can search the library catalog by author name to find books.
Here are a few places to find literary criticism about the author you picked.
Try searching the library catalog with the author's name as subject to find books and ebooks about that author.
What exactly are we searching when use these resources? Generally, the results are articles from academic journals written by literary scholars. Here's a list of academic journals in the field of children's and young adult literature. You can search directly in any one of these to find literary criticism.
Dissertations are another great source of literary criticism.