
You may not know the name, but it’s likely you’ve seen the work of Paul Manship. The Smithsonian American Art Museum site has a huge archive of his drawings and sculptures.
His sketches are excellent lessons in anatomy, composition, and construction. What surprises me most is the variety of line and technique he used in his drawings, most of which were to become streamlined art deco sculptures.
Artcyclopedia also has a list of other museum sites which feature his work, but Smithsonian has by far the best collection.