Melissa, they do not sell online, and some of their prices are not even online. You have to go into a store to buy a dress, but once you decide on a dress and know your size you can order over the phone and they will ship it to you.
Bridesmaids dresses are not on sale with the over all sale, but they do have some on the rack that are on sale, basically its a style they are getting rid of and they have certain sizes in stock and those will be cheaper, but I would not recommend counting on that, since each store has different things on the racks.
If you buy your dress there, your wedding party gets $$$ off their dress.