After reading many many posts, I would say that many of the "recruting" things don't matter until your son is in high school. The advice that comes up the most frequently and gets the most likes on the board seem to be
(1) maintaining grades
(2) taking a college admissions test as early as possible (9th grade? Early 10th grade?) so your child knows where he stands and can work to improve scores as needed
(3) tracking key statistics at home so you know when to showcase (don't showcase unless you know your son has numbers to show)
Personally, we pay (and have been paying) for hitting lessons with a very very very good teacher. Our son loves to work out, so we also pay for semi-private training at a baseball-focused gym. These are things that other HSbaseball parents find unnecessary.