Outside of a tightly circumscribed community of folk followers, Dave Moore is an unknown. Everything about the Iowa-bred songwriter and multi-instrumentalist announces the sad fact: the way his record company cavalierly passes on his home phone number without even asking what paper the inquiring writer works for; the way Moore thanks you for showing an interest in his work with a sincerity that comes from not having had the opportunity too often; and especially the way he combines homegrown folk, reverentially traditional blues, beer-crying country and squeezebox-pumping conjunto with a genre-blurring disregard for who may be -- but probably isn't -- listening. Chalk it up to prodigal talent and the naivete that often accompanies it. The thirtysomething Moore didn't get around to taking up music until age 21, when his mother's gag stocking-stuffer of a harmonica found a permanent place cradled in his cupped palms.

Moore's earliest recorded appearances came courtesy of guitar-playing session slots on the early-'80s catalog of Iowa City compadre and only slightly less underexposed fellow folkie Greg Brown. Both musicians have gained their broadest exposure through regular performances on Garrison Keillor's Prairie Home Companion radio program. Both record beautifully fat-sounding albums for Iowa's tiny but respected Red House Records, and both express themselves with booming, larger-than-life baritones that crack in all the right places.

But Moore is no Greg Brown clone. He has come to his music through a circuitous route of his own making, and he's sponged up his unorthodox influences through his own peculiar sieve of experience.

After two years of college in Iowa, and with no particular thoughts of a musical career in his head, Moore got restless and took an eight-year hike that led him through South America, Mexico and the American South, working the folk/blues singer's requisite string of factory jobs. Along the way, he started listening to seminal songster Mississippi John Hurt and developed an enduring love for Delta blues and the accordion-based musics of Mexico. "The conjunto stuff has a lot of similarities with the German polka music," he says, "only with a darker edge. I think that edge is what drew me to it in the first place."

Moore taught himself to play the guitar on the road, playing mostly traditional blues covers of songs by Hurt, Bukka White and Mance Lipscomb. But he didn't engage the guitar in earnest until his return to Iowa City in 1980. Coming off years on the road, Moore found himself attracted to the burgeoning Iowa City acoustic scene because, he says, "it seemed to have a broader conception of folk music than a more established folk center like New England. It just seemed more receptive to the Mexican and blues and roots influences." Even today, Moore says, he's best received in the Midwest, western Canada, Texas and, of all unlikely places, Italy, where he recently toured. "I was planning on playing a lot of traditional stuff, but the people who came out to see me had the album and they asked for particular songs. They knew which ones they wanted to hear. It surprised the hell out of me."

By 1981 Moore had established himself as a presence in Brown's band. A few years later, after teaching himself to play the button accordion, he recorded Jukejoints and Cantinas, a collection of Texas roadhouse blues, conjunto and norteno standards. The album was conceived as little more than a way to use excess studio time, and wasn't released until late 1985.

In the meantime, though, Moore was busily soaking up musicology. A folk apprenticeship grant from the NEA in 1985 allowed him to live in San Antonio, where he spent three months in day-to-day tutelage under Tex-Mex accordion legend Fred Zimmerle. According to Moore, it wasn't quite the guv-funded cakewalk it sounds.

"Every day I'd go to his house and he'd teach me a tune. I'd go home at night and practice it, go back in the morning, he'd correct my mistakes, and we'd go to the next one. But the cultural barriers in a situation like that can be a real mindfuck. They stopped giving that particular grant shortly after mine, because too many people weren't willing to do the work. They'd just take the money and run."

Moore took the knowledge and ran, and he returns to San Antonio at least twice a year. He began writing his own songs in 1986, and he and his group were enlisted for Prairie Home Companion's final road tour to Alaska and Hawaii. But it wasn't until 1990 that Moore's original musical ideas coalesced into the album Over My Shoulder, a varied document that touches on the traditional blues with idiosyncratic readings of Bukka White's "Fixin' to Die" and Blind Willie Johnson's story-song of the Titanic, "God Moves on the Water." The album's conjunto influence shines through with the standards "El Golfo" and "Open Up Your Heart (Abre El Corazon)." But most important, Over My Shoulder showcases Moore's own folksy songwriting with songs like the bluesy goof of "Just a Dog" and the gently prodding ode "Waitresses."

But Over My Shoulder earned its accolades in 1990, and the ensuing years have seen an unfortunate lack of product from Moore. His excuse, not surprisingly, is unassuming enough. With a wife and two kids, he's simply been too busy trying to keep his financial head above water to get into the studio.

But Moore says he's got both feet under him now, as well as a new album slated for a February release on Red House. In the meantime, he's sure to be working out the new material over the course of the present tour, playing solo with only his guitar, slide, button accordion and harmonica rack for accompaniment. Moore acknowledges, like any folkie with a rocker's heart, that he misses the presence of a drummer when he's on the road, but from the sound of his albums, and his itinerant history, he carries all he needs.

Dave Moore performs at 8:30 Thursday, May 26 at McGonigel's Mucky Duck, 2425 Norfolk, 28-5999. $5.