Most of our online databases include citations for book reviews. Do an advanced search and use the book's title and search 'book review' to narrow it down if there are too many with just the title.
Also use the specialized databases for the subject area to find more places to look than those below. For example, go to the History guide for scholarly books on history, economics, and other areas.
Remember that we also have printed services that list reviews for older books, e.g., Book Review Index (Reference Z1035 .A1 B62) for 1965 through 2008 and Book Review Digest (Reference Z 1219 .C96 [date]) for 1905 through 2001.
If you need a summary of an older book, use Masterplots (Reference PN44 .M33 1976) or one of the Masterplots II series: African American Literature Series (Reference PS153 .N5 M2645 1994), American Fiction Series (Reference PN846 .M37 1986), British and Commonwealth Fiction Series (Reference PR881 .M39 1987), Drama Series (Reference PN6112.5 .M37 1990), Women's Literature Series (Reference PN471 .M37 1995).