Similar to ebay, this auction site specializes in various aquarium products.
Suppliers of pond supplies, fountain supplies, and aquatic plants. They provide an online catalog and ordering information.
Koi and Garden Pond Specialists
A supplier of a full range of pond supplies. In addition to a catalog, this site includes a lot of good information for the hobbyist.
A popular Koi food supplier. They provide a toll free number to contact them for dealer or ordering information.