The best way to find book-length studies of an author and his/her works is to do a Subject search in ALICE for the name of the author (last name first). Here's an example of some of the search results for Charles Baudelaire:
The first line is for books about Baudelaire in general. The other lines, with his name plus "subdivisions" (aspects of him as a subject), are worth looking at as well.
Line 6 is for biographies of Baudelaire.
Line 14 indicates that there are 41 book-length critical studies of Baudelaire.
Line 22 shows that there are 20 books specifically about one of his works, Fleurs du Mal. Perusing these subject terms with their subdivisions can give you a good idea of how much we have about a particular author.
In most cases, books by an author (which you would locate by doing an Author search in ALICE) will be shelved in the same area as books about the same author. But not always: some books cover multiple authors and will be shelved in a different section of the collection.
Finally, it's always a good idea to look for the same subject in OhioLINK as well as ALICE. You'll have a lot more to choose from, and borrowing books from OhioLINK is fast, free, and easy!