Haven’t seen enough DBS ads recently? Philadelphia-based Primestar Partners plans to uncork a $150 million marketing campaign this spring to lead up to its planned launch of 65 additional channels (to its existing 95 channels) on April 20. Boxing champion emeritus George Foreman will be spokes man for Primestar’s expanded-service marketing blitz, which will begin March 5. The marketing drive will be anchored by Primestar’s sponsorship of country singer Clay Walker’s 100-city U.S. tour (in which Primestar plans to spend $1.1 million on promotions) as well as the inaugural "Primestar 500" NASCAR stock-car race in Atlanta on March 9. "Our research indicates that NASCAR fans mirror our demo graphics, and represent a growing segment of Americans who are potential Primestar customers," the company said. Primestar also will be at all 33 NASCAR races through its racing team, which is co-sponsored by the Family Channel. Primestar retails its equipment directly through an "800" number as well as through RadioShack outlets. (Primestar Partners, 610/617-5446.)