Guayaberas may now be ubiquitous, as familiar a sight in South Beach as in Little Havana, as popular with club-hopping twentysomethings as with potbellied old men. But there is still only one mago de la guayabera (guayabera magician): Ramon Puig, owner of La Casa de las Guayaberas, the famed Miami emporium. The Cuban-born Puig has been making guayaberas for more than 60 years. His client list has included Cuban President Carlos Prio as well as U.S. presidents Ronald Reagan, George Bush, and Bill Clinton. The man has stories, and he'll gladly share them with anyone who wanders into his shop. But the guayaberas -- gorgeous creations in a variety of fabrics and colors -- are a different matter. Those he'll charge you for.