Help? OPI Nail Polishes?

I'm going to Vegas in July, and I really want to buy some OPI nail polishes! There's none around where I live, so I'd love to be able to get some, but I'm not sure where they sell them. I'm going to be around "The Strip", where all the hotels are. Does anyone know if they sell OPIs in any hotels or something? And can you guys recommend some good OPI colors you like? :) I really want to buy them in stores, not online.