Milliken's Bend is covered somewhat at the Vicksburg National Battlefield Park. There is no museum near the site of the battle and probably only one or two historical markers. I doubt that anyone has done a DVD that covers the fighting. Several years ago, Professor John David Smith served as editor for a book on black soldiers in the Union army, and one of the essays in the book provides really good coverage of the battle. I believe the book was published by University of North Carolina Press. You should be able to get the title and price on Amazon.com by searching under his name as author.