Dress shopping for an event isn't always the best experience so I thought I would offer a shopping tip that works for me.
Think of the stores that you would like to visit and go online to their website. Many stores like Forever 21 (that offer one-stop clothing/accessory/shoe shopping) have their clothing online now and many of the same styles can be found in-store as well.
I like to pick out a handful of looks with accessories and shoes, make a collage from the thumbnails and print it out then go to the store and see if they offer the same styles. If this is done, I know exactly what I need before going into the store, thus saving time browsing. If things catch your eye, great! Grab them and add to the trying on!
You should find a look that will suit your event and in half the time!!!