Help me pick a prom dress?

Okay, so our prom is in a few months, and the theme is "Around the World". This means we should try and find dresses native to other countries. For example, one of my friends is dressing in a sari (this one, if you're curious: http://www.utsavsarees.com/store/sarees-large.aspx?icode=SLSKK9495 ) and my other friend is dressing in a cheongsam (http://www.made-in-china.com/showroom/annahe/product-detailabemiZBOAEVl/China-Cheongsam-8004-.html) ((they're both girls)). I want to find a dress too, but I'd rather not have a sari or cheongsam, (since the three of us would be together a lot that evening) so could I get some help picking a dress? I only need a general idea (like "sari", etc.). I'm sure I could find the perfect dress if I only knew where to search.