You can sell used rock climbing equipment online at eBay where people will bid on the item and pay you usually through an online service such as PayPal. You can also post a listing of the equipment on Craigslist along with your contact information and people will get a hold of you to purchase your items.
It will obviously depend on your location. However, one chain, REI, is prevalent throughout the United States. They sell rock-climbing equipment and are generally known for their knowledgeable staff.
Professional climbing gear can be bought online at REI or Dicks or Eastern Mountain Sports or www.campmor.com or www.mountaingear.com. These stores also sell equipment online.
You can find climbing gear at almost any good sports store such as ACME Climbing. I you need a list of retail stores that sell climbing gear you might try http://www.summitpost.org/online
There is a Fitness depot online and it can be found on eBay where people sell their Fitness equipment. There are also retailers online that sell Fitness equipment.
Hoopers sells products such as camping and hiking equipment and climbing gear. You can view all the products that are available from Hoopers online at the Hoopers Network website.
There are several well known online retailers that sell a wide variety of both new and used excavating equipment, including Iron Planet, Construction Equipment, Rock & Dirt, and Ennis Equipment. One can also rent excavating equipment online at Neff Rental, Sunbelt Rentals, and United Rentals.
The Kletterseil company is a German company which makes sporting equipment products. The sporting equipment products which they sell are climbing ropes.
Craghoppers sell clothes for outdoor activities. These include clothing for travel and adventure such as climbing equipment and jackets for cold weather.
Antique farm equipment can be sold online at Ebay.com. Another site that specializes in farm equipment specifically is USfarmer.com.
Most people, when attempting to sell used equipment online, will choose eBay. The online business allows buyers and sellers a safe marketplace to list and purchase products.
You can sell used weight training equipment on Craigslist. You can also auction it off on eBay.
There are a lot of places that sell table tennis equipment; you can find them online or in stores. Megaspin and Paddlepalace sell all kinds of equipment.