Cell phone whole sellers in Chicago?

im going to be going to Chicago to go birthday hunting for my brother just turned 20, and im looking for a new cellphone for him and one for myself as well. i heard from a couple people that said that you can get really good wholesale priced phones in Chicago, now i would like to know does anyone know any stores in Chicago that these people might be talking about? phones like the pantech duo which im looking for and samsung blackjacks etc.. any info would be appreciated thanks