family video has got some cheap games, some of the $20 ones are moderately good, they get progressively better as the price increases, but you'll still get a break from the $55-60 you'll pay most places.
shipping is usually 1.99/order, not dependent on the number of games is my understanding
http://www.familyvideo.com/catalog/browse_games.php?so=asc&sb=products_price&browse_id=48