Use these databases and websites to search for academic book reviews:
*Historical Abstracts (EBSCO) (Using the Advanced Search Screens, Select Document Type: Book Review
H-Net Reviews - Reviewing books is a primary mission of of H-Net. While print journals generally take a year or more to review new publications, H-Net obtains and distributes professional reviews in just months.
*JSTOR (Using the Advanced Search Screen, select item type: Review)
Reviews in History - Reviews of books and digital resources
*Web of Science (Using the Advanced Search Screen, restrict results to Book Review)