Andy Roddick is planning to marry 20-year-old model Brooklyn Decker. “The couple wanted to tell their family and close friends first but good news travels fast,” said a note on Roddick’s Web site. “With their hectic travel schedules, Andy and Brooklyn plan to enjoy their engagement and will wait to set a wedding date.” Decker has appeared as a swimsuit model in Sports Illustrated magazine. The couple began dating in 2007 when Roddick, 25, asked his agent to track down a number for Decker, 20.