Socket adapters for light bulbs can be purchased from websites such as Lowe's, Amazon and ACE Hardware. As of 2015, the Lowe's website sells 13 different kinds of light bulb socket adapters that range in price from $1.99 to $7.68.
The cheaper socket adapters that are sold at Lowe's are used to change a light socket to an electrical outlet. The more expensive socket adapter products provide up to two additional electrical outlets, as well as a light bulb socket.
The Amazon website sells socket adapters that can either be used to convert a light socket to an electrical outlet, or provide multiple light sockets from a single outlet. Prices for socket adapters on Amazon range from $2.99 for standard socket adapters, to over $200 for socket adapters that are housed in custom made lamps.
The ACE Hardware website has 75 different kinds of socket adapters at various prices. The website's inventory includes Jandorf brass pull-chain and knob sockets, as well as multi-light socket adapters. Prices range from $2.99 for a Leviton socket-plug adapter, to $14.99 for a Pass and Seymour 3-way porcelain knob socket adapter. The website provides users with a store locator search feature that is organized by zip code, as well as free store pickup for products purchased online through the ACE website.