(FORTUNE Small Business) – The use of search engines to sniff out and compare products "has become the new interface of commerce," writes John Battelle in The Search: How Google and Its Rivals Rewrote the Rules of Business and Transformed Our Culture, published this month. Battelle, a founding editor of Wired and The Industry Standard, points out that aggregating every Google search--from a terrorist's bombmaking research to an anxious adolescent's hunt for acne medication--yields a database of humankind's wants and fears, manna for savvy entrepreneurs. But business owners who depend on Google can find themselves vulnerable. Battelle tells of one online shoe shop that saw sales plummet overnight when Google tweaked its algorithms, knocking the store from the top of the search-results list. The ability to create or crush small businesses as an afterthought was once the exclusive domain of the government. What happens when you give that sort of clout to a corporation? While short on answers, Battelle raises smart and fascinating questions. --TAHL RAZ