@abl, unless you are going with a tan linen suit or something that truly clashes with black (navy does not), wear black shoes for your wedding. They will look great with a light grey suit or even darker suits. AE Park Avenues in black will be fine. I would not wear a tuxedo to this wedding. I love black tie as much as the next guy and try to find an excuse to wear my tuxedo when I can, but not for a 3:00PM ceremony, especially not one that is outdoors during the summer. A light grey suit in a lighter wool that is half or quarter lined is not a bad choice. If their suits fit you well, SuitSupply is a pretty decent option. Wear a light grey suit with a white shirt and either a wedding tie or a nice navy solid.