Dress for 16 birthday partyy?

ok so.. im 13, size 0-1 pants size, and usually a small in shirt size.. im 4 foot 10.. my sister is having her 16th birthday party at the casino at a nice restaurant, and i need a nice dress.. any1 have any ideas or pics? its not like super-duper ultra fancy, but a black or sundress with like sparkles or something would work.. so if u guys could find pics or any websites i'd like 2 c them please! thanx