HARPER SMITH/Acorn Newspapers SOUTHERN CALIFORNIA, A MAGNET FOR GIRLS' SOFTBALL-- Haley Martin, 10, of Madrona Elementary School hits the ball on Opening Day last Saturday for Newbury Park Girls' Softball. More than 20 softball teams took part. College recruiters work hard in Southern California because of the caliber of play, the coaching and the weather. This Saturday, incidentally, will be Opening Day for Little League baseball in Thousand Oaks and Westlake Village. Spring begins March 21.