When little girls spend their math classes daydreaming of weddings (instead of winning the World Series — not to say you can't do both), what do they dream of first? The perfect wedding dress, of course: a gown in white satin with a bustle and sweeping train, the perfect embellishments, and the perfect shoes. The wedding dress may be a major expense. When shopping for your dress, consider dresses that may not be categorized as a wedding dress. A bridesmaid dress could be perfect and not as…