Playing in just his eighth NHL game, LaBarbera made 19 saves to earn his third victory in three starts this season.
"I just want to get better every day and improve my game," said LaBarbera. "It's a long, long season. You build your confidence as you go along."
LaBarbera came within 11 minutes of earning his first NHL shutout before Nikolai Zherdev scored his first goal of the season.
"It was a point shot that snuck through, I didn't see it," said the 25-year-old netminder, who was signed by the Kings as a free agent this summer.
He has allowed just four goals in his three starts and stopped 69 of 73 shots while sharing the Kings' goaltending duties with Mathieu Garon.
Last season, LaBarera had a 1.84 goals-against-average with Hartford in the AHL, the second-best GAA in the league.
The victory was the fourth in a five-game homestand for the Kings (4-2) that ended Sunday.
"It's a good start for us, now we have to keep it going," said LaBarbera.
The Blue Jackets (1-5) ended a four-game road trip with a third consecutive loss.
"This trip leaves us with question marks instead of solidifying the team and building chemistry," said Columbus goalie Marc Denis.
The Blue Jackets entered the game with the eighth-best penalty killing unit in the NHL, but could not overcome early penalty problems.
"When you're killing penalties all the time it puts too much on the team and they can't expect to catch up," said Columbus coach Gerard Gallant.
The Kings had a two-man power play advantage eight minutes into the game when Armstrong's pass through the crease deflected off the skate of Columbus defenseman Duvie Westcott into the net.
Cammalleri made it 2-0 by firing a 45-foot slap shot past goalie Marc Denis during another Kings power play with just 1:07 left in the first period.
"We had some good puck movement and a lot of support -- that's what you need on the power play," said Cammalleri, who also assisted on Armstrong's goal.
He has four points (1 goal, 3 assists) in three games since returning to the Kings' lineup. Cammalleri was a healthy scratch in two Kings games last week.
Alexander Frolov scored just as a second-period power play ended to push the Kings to a three-goal advantage.
- Kings LW Luc Robitaille didn't play because of a groin injury and Ken Belanger made his season debut in Robitaille's place. Belanger hadn't played in an NHL regular-season game since Nov. 5, 2002, when he sustained a concussion at San Jose. He retired from hockey for two years before being offered a tryout and making the Kings this season.
- Columbus forward Dan Fritsche left the game with an ankle injury in the first period and didn't return.