Craft-centered websites such as DickBlick.com offer patterned folding paper in various sizes and amounts per package. Brick and mortar craft stores, such as Hobby Lobby, also offer a variety of choices in patterned folding paper.
Amazon.com offers patterned folding paper, or origami paper, complete with links for books that give folding patterns. It also offers a selection of patterned folding paper from foreign countries, such as Japan, where this is a popular pastime.
The best variety in selection is found at craft stores. Department stores such as Wal-Mart offer origami paper for folding, but many of their selections are for beginners, and there is not a large selection of patterned paper, as of 2015.