If you are doing a few rows at a time, this is the best that I have come up with http://www.worthpoint.com/worthopedia/acme-corn-planter-seeder-vintage-garden-tool  This planter came with a set of plates with different size wells so if you buy one, make sure that it has 3 or 4. If the plates are there, they will typically be inside of the seed reservoir. If you are doing an acre, get the Earthway or a good clone.