I know what you're thinking: Ann Taylor for bridesmaid dresses? Reeeeeeally? But check out these two gems, and see if you don't agree that they're pretty darn gorgeous (and universally flattering!).
And to make the most of this one's Grecian vibe, I'd swap the necklace for big, dramatic earrings, and add flat metallic sandals. If you're tall, forgoing heels is a great way to ensure that a long dress skims the ground. To me, there's nothing worse than that awkward ankle length.