Don't forget book reviews! Most databases will allow you to select book reviews as a source type. Reason: find out a book's reputation, any hidden context, its significance among experts, and any problems with the book. Most authors are pretty persuasive and you need a second opinion.
Be sure to limit by document type check box
New York Times archives is a good option for nonacademic books published before 2006.
Your best bets for economics are:
Econlit, Business Source and JSTOR.
Be sure to limit results to "review" or "book review," depending on the interface. In Business Source Complete, you gotta click Show More types, and then choose doc types.
You can also use these databases:
InfoTrac Small Business Collection - focuses on less scholarly and practical titles - current management techniques and real world advice about business topics. You can search by book title or type your subject and then "book review."
Wilson OmniFile FullText. A good grabbag. You can limit it to search "book reviews" by a particular. discipline
These are not your only options but are some of the best. You can always check your favorite database to see if it has book reviews.