Ten years ago John Caparulo was desperate to get a Tuesday amateur-night spot at the Funny Bone in Station Square. By 2005, the East Liverpool comedian was on a nationwide tour with movie star Vince Vaughn, awkwardly fielding requests to autograph women's breasts.

Naturally, the eastern Ohio guy -- whose parents can pick up this newspaper at their corner market -- had no idea how to react. (He initialed them instead.)

"Honestly, for me I'm still very, very small town and old- fashioned and I'm not the type who's good at taking advantage of groupie situations," the self-effacing 32-year-old said. "While other guys are getting a quickie in the bathroom ... I'd meet a girl and be like, 'Maybe she'll be my wife someday.' "

Most touring comics play to small crowds of a couple of dozen people on weekday nights, biding their time for the big crowds and paydays on the weekend. During the filming of "Vince Vaughn's Wild West Comedy Show" -- which follows a 30-day nationwide bus tour by Caparulo, three other comics, Vaughn and some actor buddies -- life was a little different.

"With this thing every night was an event," Caparulo said during an interview in a Downtown hotel last week. "It was the biggest thing happening in that city that night, and it was all because of Vince."

That's because the tour was filmed during the summer of 2005, when Vaughn's "Wedding Crashers" was in theaters, going on to become the second-highest grossing R-rated movie ever. Two years earlier, he had starred in another comedy hit, "Old School," and the theaters were packed every night with fans, many of them young women.

"It was colossal. It was really like going on a rock 'n' roll tour," Caparulo said.

Vaughn has haunted comedy clubs for years and thinks of stand-up as "one of the last untouched art forms," said the movie's director Ari Sandel. Vaughn knew Caparulo and the other comics for years, and picked the Ohio native because the Chicagoan wanted a fellow Midwesterner on the tour.

The 2005 summer was also marked by Hurricanes Katrina and Rita, which hit just before the tour bus was due to swing through New Orleans and other parts of the Gulf Coast. That injects some gravity into the film (the comics visit an evacuee camp and host fund-raisers), which gets deeper when it explores the troubled family lives of two of the comics.

"What we didn't expect until we were on tour is how much you really start to root for these guys," Sandel said this week. "There is a human element to this story. It could just be jokes and guys on stage -- while it starts off with comedy and hijinks, it becomes a story about four guys on the road trying to achieve their dreams."

One comic talks about his immigrant father not speaking to him for years. Another talks about having a funnier older brother who died of AIDS. That kind of family pain has always been a component in comedy, which makes Caparulo's story all the more interesting: his parents are his biggest fans. They are also funny.

In the film Caparulo says his father John, a former mechanic who teaches at Youngstown State, is a "bitter old man" who bought him Richard Pryor records when he was a boy. In her East Liverpool living room, Jeanne Caparulo jokes her son was destined to be an "entertainer, cult leader or convicted felon."

"No matter how many times I watch [the scene], I get choked up when I see it," Caparulo said last week. Talking to a reporter in the same regular-guy clothes he wears on stage -- a ballcap and a T-shirt -- he said, "When I started this whole thing, it reminded me of how supportive they were and how lucky I was to have a family like that."

A year after graduating from Kent State in 1998, Caparulo left Ohio for Los Angeles and worked his way up the Sunset Strip comedy scene, starting as a doorman at the Comedy Store. He is part of the "Blue Collar Comedy: The Next Generation" troupe, had a special on Comedy Central and has appeared three times on the "Tonight Show," including a visit last month. He shoots a new DVD May 3 in Cleveland.

There is something odd about the exposure Caparulo is getting now for going on a raucous tour with a movie star -- he admits he rarely leaves Los Angeles and doesn't tour as other comedians do.

"I never wanted to turn comedy into something that felt like work. Going on the road, staying at a Days Inn, grinding that out -- I didn't want to make myself hate comedy," he said last week. "I made it, so I never really had to grow up."