At WDW they are also called the Dapper Dans. If you know any barbershop songs, they will also let you sing with them- quite a thrill. (I've still got my honorary membership card!)
They used to hang out at the barbershop (periodically dropping in for an impromtu performance) , but are not there as often now that the shop has moved next to the firestation/horsebarn on Main Street. They still perform daily on Main Street and will do requests at times.
Enjoy!