"Championship Ballroom Dancing," taped at the Ohio Star Ball, used to show on PBS every Februrary and then repeated throughout the year.
Unfortunately, the last year that the OSB competitions were taped was 1999. In 2000 they taped a special 20th anniversary edition show. And then in 2001, they didn't tape anything. The producer then decided to move on to other things, and no one could get funding together for another production, so it hasn't been taped since.
However...on June 1st you can watch "Dancing with the Stars" on ABC-TV at 9pm (I think, check local listings for time etc.).