Charles Marion Russell (1864-1926) was such an important and prolific Western artist, his works can be found in over 50 museums (and countless galleries, I'm sure) in the United States and even around the world.
Russell was proficient in several mediums. He painted in oils, gouache (a type of watercolor), and sculpted. You will find that you can view many copies of his popular cast-bronze sculptures in a number of venues, because bronzes are made by pouring molten metal into a mold made from the original piece of artwork. Bronze pieces are usually made in limited quantities at a foundry. The numbered copies of these bronzes are very collectible, with the first editions, usually numbered on the sculpture like a print. Most Western art museums contain at least a few works by this influential artist.
Russell's representational style included cowboys, indians, and landscapes inspired by visits to National Parks, California, Arizona, and Colorado. The color palettes are muted, but realistic, and his paintings and sculptures are dominated by a sense of movement and action. Russell depicted a mythic American West.
Charles Russell's paintings are more valuable than his sculpture, simply because their numbers are fewer. However, his sculpture is probably what he is best known for, again, because it is so prolific.