After his playing career ended, LaMacchia spent six decades as a scout with the Philadelphia Phillies, Atlanta Braves, Toronto Blue Jays, Tampa Bay Rays, and Los Angeles Dodgers, during which time he discovered dozens of players who made it to the major leagues.

LaMacchia eschewed the use of computers, radar guns and stop watches as scouting tools, saying "I trust my eyes... Been good so far".

[3] He is credited with having scouted players including George Bell, Cito Gaston, Dale Murphy, Dave Stieb, Rocco Baldelli, and David Wells.

He convinced Dodgers General Manager Ned Colletti to pursue outfielder Andre Ethier, who had been playing in the Oakland A's organization.

[5] LaMacchia died at age 89 on September 15, 2010, at his home in San Antonio, Texas, after having experienced a stroke in the weeks before his death.