WITH GUITARS BLASTING AND the spotlight reflecting on his glasses, Frank Gonzales might as well be dreaming. A Foreigner fan since grade school, he has spent most of his 27 years wishing he could sing a duet with lead singer Lou Gramm. "I mean, you want that sort of thing to happen," the soft-spoken audio technician from El Paso confides. "But you don't expect it to." Still, that is definitely Gramm next to him onstage, and as Foreigner backup musicians Bob Mayo and Mark Rivera lead the way into the band's 1978 hit "Double Vision," Gonzales bears down to snarl the first verse. "Feelin' down and dirty, feelin' kinda mean..." Gramm takes the second verse, and as they join forces on the chorus, the chandelier above this hotel ballroom is literally rattling with the sound of a rock and roll fantasy becoming reality.

Quite a moment. And just another late-night jam session at the Rock n' Roll Fantasy Camp. Based on baseball fantasy camps and held at Miami Beach's Eden Roc Resort Hotel in April, the four-day convention—the first in a series planned, for various locations, by concert promoter David Fishof and Arkansas entrepreneurs John and Marsha Phillips—is a combination music seminar, backstage party and open-mike night with the stars. For $2,795 (plus airfare), about 35 music fans have the chance to pick up a few new riffs as well as take meals, lounge poolside and even share a stage with the likes of Bruce Springsteen's E Street guitarist Nils Lofgren, Grand Funk frontman Mark Earner, the Rascals' Felix Cavaliere and '70s guitar hero Rick Derringer.

"It's everyone's rock dream," says Fishof. Which accounts not only for the starstruck expressions on the campers' faces but also the ironic amusement of the musicians who know better. "It's no fantasy life," sighs Clarence Clemons, Lofgren's E Street bandmate and a drop-in celeb (as was Beach Boy Mike Love) at the camp. "But it's a life. And you've got to follow your dreams."

For Foreigner buff Gonzales and his fellow campers, that pursuit has led to the fantasy camp's kick-off dinner at the swank Astor Place Bar & Grill in Miami's South Beach. Two days before his duet with Gramm, Gonzales cradles a 7 Up and peers at his idol, who stands near the 12-foot, blow-up jukebox looming above the Hotel Astor's pool. "When I heard Lou was going to be here, I said, That's it. I'm going.' I didn't care how much it cost."

Neither did Linda Hulick, who used her upcoming 40th birthday to leverage her husband into letting her make the trip from Denver to the stage of her dreams. As she watches Lofgren, Derringer and the other musicians perform a set of Beatles songs and blues standards, Hulick admits she would happily trade her job as a sonographer for rock stardom. "I've always wanted to be onstage," she says. "Giving your all to an audience and hearing them respond. That's magic."

When the classes begin the next morning, Nils Lofgren tries to explain that spell to a meeting room full of would-be guitarists. "Once you get that groove going, you never want it to end," he says, coaxing a bluesy riff from his scuffed Fender. At 45, Lofgren has approximately the same suburban background shared by the middle-aged doctors, lawyers and execs facing him. Most of them have played music for years, but Lofgren functions on a different level. He radiates rock and roll, from his black high-tops to his spiky (if silver-flecked) sideburns and loose-limbed slouch—yet it's nearly impossible for him to describe how to play it well. "When you find something that feels good for your body," Lofgren says finally, "stick with it."

If the spirit of rock and roll is hard to describe in a lecture, it's easier to get across when the campers take up the drums, keyboards, guitars and microphones set up at the front of the rooms. "It's gotta be a little sloppy, man," cries Mark Rivera, camp music director (and multi-instrumentalist for Foreigner, Billy Joel and a host of other A-list types), as he leads the count-in to the Rolling Stones' "Honky Tonk Women." "This is rock and roll, right?" Rivera signals the drummer—a Boca Raton exec named Gary Brown—and with Bob Mayo on guitar, a Florida internist named Jeff Dash on bass, a couple of journalists manning the keyboards, Linda Hulick on backup vocals and Rivera wailing the lead, the classroom rocks with surprising conviction.

Afterward, Brown shakes his head in wonder. "I haven't played like that in 20 years!" A pro drummer on the Florida circuit during the 70s, Brown played studio sessions with the likes of the Bee Gees before trading his drums for a career as a health care center CEO. Success was its own reward for a time, but when Brown discovered last year, at 40, that he needed surgery to correct a heart disorder, he felt drawn back to music. "Once you get that feeling, it never goes away," he says. "And my attitude now is to have a good time."

That the Gary Browns of the world would pay big money for this kind of good time—unlimited access to the talents behind, say, "Rock n' Roll Hoochie Coo"—first occurred to David Fishof backstage at one of the Ringo Starr concerts he produced in 1989: "The stories I was hearing were fantastic! I was transfixed!" Deciding to retail his experience, Fishof partnered with business-magnate pal John Phillips, who had sold his supermarket chain to Wal-Mart and was looking for new ventures. With Rivera onboard as musical director, they recruited an array of "patient, friendly and talkative" rock veterans, offered a set wage (the same for each musician, no matter their relative fame) and deluxe accommodations. "The pay isn't going to stop the world," admits Rivera, a 44-year-old father of two whose yearning for a more normal life has led him to study for a securities trading license. "But this could grow into a franchise. It's a good thing to have in the future."

For Gary Brown, who provided the beat for Gonzales's triumphant "Double Vision," his dose of rock and roll will be a glorious part of his past: "I was onstage with Foreigner! [Elton John bassist] Bob Birch locked his eyes on me. He was smiling, I was smiling. We were in the pocket." And for the moment, at least, it was no fantasy.