Begin by checking out tennis magazines for reviews of tennis racquets, or simply go to a sporting goods or tennis specialty store to peruse the selection of tennis rackets.
Amazon.com has a Tennis & Racquet Sports department providing sales of racquets in such categories as advanced, beginner and intermediate.
Tennis Warehouse All the best name brand tennis racquets can be found for sale here, including ones by Prince, Estusa, Head and Fischer.
Also be aware of head size and string tension with the tennis racquets you're considering.
However, always be sure to test tennis racquets out in person before buying one online.
You may be able to find some of your best deals on tennis racquets by shopping online.
Tennis Company offers great deals on racquets by Yonex, Kennex and Tecnifibre.