"Monica's Story blew me away," Manhattan-based political consultant Peter Feld wrote in the customer comments section of Amazon's Web site.
But Feld said Tuesday he was simply having fun with a fabricated critique.
"I wrote a review that I made up out of thin air," he said. "I did it out of humor and admiration for Monica."
The 288-page book by British author Andrew Morton, based on exclusive interviews with Lewinsky, is due out this month. Messages left with the publisher, St. Martin's Press, were not returned Tuesday.
Customer comments and reviews can be sent electronically to Amazon.com, which does not contact the self-made critics to ensure that they've actually read the books.
The Monica reviews will be deleted, said Bill Curry, a spokesman for the Seattle-based company, the world's largest online bookseller.
Aside from negative publicity over the Lewinsky book, Amazon.com had been criticized in recent weeks for its policy for reviewing certain books. Cooperative advertising agreements buy book publishers prominent display on its home page and either author interviews or Amazon.com reviews.
The company announced Tuesday that it would provide customer refunds for books reviewed under such agreements.