Cellular breaks an $8.5 million regional campaign during this Sunday's Super Bowl XXX. The campaign, by Tucker Wayne/Luckie, Atlanta, features Olympic athletes and will run through June in print, TV, radio and outdoor. Separately, BellSouth Cellular has signed Atlanta Hawks coach Lenny Wilkens as its new spokesman. Mr. Wilkens, also coach of the 1996 U.S. Olympic basketball team, is the centerpiece of a new sweepstakes promotion BellSouth is promoting. Five first-prize winners will be awarded a trip for two with tickets and accommodations to this summer's Olympics in Atlanta.