Locks for sliding patio doors can be purchased online from hardware store websites such those of Home Depot and Lowe's, as well as from online-only retailers such as Amazon. Internet auction sites also sell various sliding patio door locks and accessories, many of which are used.
The Lowe's website allows users to browse a wide selection of sliding patio door accessories, including locking mechanisms. All search results on the site can be filtered by customer rating, price range and brand. Each listing contains pricing information, along with the product's item number for the store's inventory system, the model number provided by the manufacturer and a description of the part and its function. The site also allows users to see if specific parts are available in nearby retail locations, along with tools to have the item reserved prior to visiting.
Amazon offers an in-depth customer review system for all of its products, including sliding patio door locks. Each review consists of a numerical rating ranging from one to five, along with a written summary of the buyer's experience. Users are able to rate each review based on how helpful it was, with the most helpful positive and negative reviews featured at the top.