Lulus.com: Fun, feminine and flirty dresses that are always on-trend. Last time I checked they had 348 styles to choose from, with dozens priced under $50. I also love this strapless painted iris dress ($38) with an exposed zipper, pair it with a cropped jacket or cardigan for a graduation ceremony.
ModCloth.com: With their expansive selection of retro, indie and vintage dresses, ModCloth shoppers won't get caught wearing the same dress as any other girl at their event. If you can splurge, this Pralines & Creme dress is close to perfection ($130).
ShabbyApple.com: Shabby Apple delivers sexy dresses with modest cuts and figure-flattery in mind. Think Jackie O. and Katherine Hepburn, on a budget. They also have pretty dresses for moms-to-be, including this Bow Baby black maternity dress ($72).