Towel racks for outdoor pools can be found online at Amazon.com, Frontgate, and Ballard Designs. They can also be found in brick-and-mortar stores such as Walmart and Bed Bath & Beyond, depending on the store location.
Amazon.com offers a wide selection of towel racks for outdoor pool use ranging in price from around $40 to several hundred dollars, as of 2015. Ballard Designs and Frontgate offer higher end towel racks. While Ballard Designs only carries a small selection of freestanding racks, Frontgate offers both freestanding racks and outdoor towel hooks to hang on the wall.
Walmart and Bed Bath & Beyond sell smaller selections of towel racks but offer shoppers the convenience of purchasing racks in-store without needing to order online.