The couple wed on March 19 at the Teton County Courthouse in Choteau, Montana, in a ceremony that "lasted five to 10 minutes," Lisa Sinton, Clerk of District Court in Teton County, told Access Hollywood.
Letterman announced the nuptials during the taping of Monday's "The Late Show with David Letterman."
"I had avoided getting married pretty good for, like, 23 years, and I - honestly, whether this happened or not - I secretly felt that men who were married admired me…like I was the last of the real gunslingers, you know what I'm saying?" he joked.
During the brief ceremony, Regina wore "a blue suit and a corsage" while Letterman "had on a sweater and was casual," Sinton added.
When the "Late Show" host made the big announcement during his show, some of the people in the audience weren't entirely sure it was for real.
"We thought it was a joke at first," one audience member told Access after the taping.
"When we realized he was serious, everybody really started to cheer," another audience member added.
However, things didn't go quite as planned when Letterman, 61, Lasko, 48, and the couple's 5-year-old son, Harry, hopped in the truck to head to the Montana courthouse.
"It's me, Regina and Harry in the pickup truck… we get two miles from the house and we get stuck in the mud – I mean, turn the truck over, stuck in the mud. So now we think, 'Well, somebody will come' – no, nobody comes along," Letterman recounted. "So I get out of the truck and I walk two miles back to the house into a 50 mile an hour wind… And the whole way, I'm thinking, 'See, smart ass, see, see, you try to get married, this is what happens.'"
And when they ran into trouble, the couple phoned the courthouse to let them know.
"They called and said they slid off the road and they would be late," Sinton noted.
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PLAY IT NOW: David Letterman Announces His Marriage To Regina Lasko (March 23, 2009)
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