Book reviews are useful sources of information, though they are not peer-reviewed sources. Book reviews can be used to determine the content and quality of a book that you find in a bibliography or WorldCat so that you can decide whether or not to request the book via ILL or Pascal. They also give you insight into the scholarly world's reaction to a particular title and often summarize the author's main arguments.
The easiest way to locate book reviews in OneSearch is to use the Advanced Search screen, which is accessed by clicking the "Advanced" link to the right of the search box on the results screen.
Next, type the book's title in quotation marks into the first search field, then choose "Book Review" from the "Show Content Type" menu.
Depending on how common your book title is and how many results you retrieve, you may want to include the author's name in your search as well. Click on "Full Text Online" to download the book review.