Al Costa's a gumshoe. But he's not your average peeper. Instead of a pistol, Costa packs a Mac

Traveling down Highway 49 in northern California's Mother Lode country, and everything's jake. An open road, blaze of blue sky, trees decked out in their autumn best like a floozy with her war paint on. The air is so clear and cool and fresh it makes a fella feel clean just to be breathing it.

Al Costa's tired Toyota four-banger is the only jalopy on this mountain road. Al's a P.I. You know -- a private investigator. A shamus. But this dick's not your average peeper. Instead of using shoe leather and sweet talk to collar wise guys, Costa tracks people down the modern way: he lets computers do the searching.

Costa hails from Sonora, an old gold-rush burg that sits about 72 miles west of Yosemite National Park. He keeps a cramped office down in the cellar of his house, space he shares with Linda "L. J." Davis -- his sidekick of 14 years. Then there's the new kid on the team, Debbie Gould, along with a flush of dogs underfoot and a couple of cats with an attitude.

A clutter of tired office furniture fills the room. On Costa's desk is his computer. Nothing fancy, just a middle-of-the-road Macintosh Performa 450 with a poky 2,400-baud modem inside. This guy's no cutting-edge, tech-head detective; he just needs something to get the job done.

That job is to get the dope on the likes of bad guys, on fathers who've deserted their families, on missing or abducted kids. Costa uses Mac and modem to call up the 11 information databases he subscribes to. He's a state-approved registered information provider. He has to be; that title greases the skids to get him the inside dope the average Joe can't get hold of. Give him a guy's name, maybe a date of birth or a social security number, and within hours, sometimes minutes, Costa can get the goods on the guy's address, the names of the little woman and the kids, his bank balance, property owned, whom he owes money to, his unlisted phone number, court filings, credit reports, any marriages or divorces, voter registration, motor-vehicle records, stocks, you name it. The cost to most clients isn't bad, either: between 29 and 500 bucks plus legwork, depending on how tough the search turns out to be. And it's all on the up-and-up. It has to be. Costa's wife, Eleanor Provost, is a regular real-life Roy Bean, the only traveling circuit judge in the state of California who happens to be a dame.

So what's it like, sleuthing from the office? A piece of cake? No knocking on strangers' doors only to be greeted by the business end of a shotgun, no all-night surveillances, no run-ins with knuckle draggers? Matter of fact, Costa's seen all that and more in his 34 years as a dick, most of it spent the old-fashioned way. But a few years ago the idea of taking a load off while letting his fingers do the two-step on the keyboard started to grow on him. "I'm 63, so yeah, I figured it was time to do it easier. But there's always money to be made supplying information to people. Computers just make it a hell of a lot more efficient." Costa may be 63, but he looks 10 years younger -- an energetic lug with a full head of salt-and-pepper hair, only a couple pounds over fighting weight. A guy with a quick smile, the type who'll grab the check before it hits the table.

Here's the skinny on a typical search, one he describes as a "four-handkerchief" affair. Ten years ago a Korean War Association buddy named Bill McClanahan approached Costa, asking for help in tracking down his daughter, Tami Lou, whom he hadn't seen in 25 years. Seems after their divorce in 1965, his ex took off with the kid. McClanahan, a deputy, finally tracked her down in Great Falls, Mont., where a court granted him custody of Tami Lou, then two. During a visit, though, the ex took the girl out for ice cream and never came back. After that, the trail grew cold.

Ten years ago, in his precomputer days, there was nothing Costa could do. But when the two got to jawing a while back, McClanahan, aware of Costa's computer searches, asks again if he'd try.

Costa figures what the hell. That night, armed with the names of the ex-wife and the daughter, Costa starts poking around. Sitting at his computer, he calls up a database called Infotek. Does a search for Tami Lou McClanahan, the daughter, checking real property records. Nothing comes up. Next tries the mother. Nothing. Then looks under the mother's maiden name. Nothing again. Hmm.

Costa runs a second check, this one based on recorded births. Confirms a Tami Lou McClanahan had been born in Cascade County, Mont. Using a second, business database, Costa runs a search for the names of local hospitals, figuring maybe they have other records on file with more information. He finds one -- Choteau Mountain Hospital -- but when he searches for a phone number, he finds the place closed down. Costa scratches his head. Next he tries to get Cascade County records, but that's a no go. Seems the county is too backwater to be on-line. Costa has hit a cul-de-sac.

Turning to another database, one called Investigators on Network that lists some 4,700 P.I.'s nationwide, Costa contacts a local Great Falls gumshoe; asks him to hightail it to the local courthouse to see what he can see.

Couple of days go by. Costa moves on to other things. Then the guy calls back -- he's found the microfiche records, found the birth certificate. It was batched with other documents that yielded the names Guy and Lou M., who apparently are related to Tami Lou. Another check finds that Guy is dead, but Lou is alive. Costa goes back to the Mac, looking for a Lou M. in a national phone directory. No listing. Next does an unlisted phone-number check and bingo -- there's a Lou M. in Great Falls.

Costa calls and gets Lou. Does some sweet talking. Turns out she's the kid's grandmother. She'd disowned her daughter, Tami Lou's mother, after her daughter had abandoned Tami Lou when the girl was 13. Lou and her husband, Guy, had taken Tami Lou in, raised her as if she were their own.

Then the woman clams up. Al wheedles. He cajoles. Finally gets out of her that she's lost track of Tami Lou. Last she knew, Tami Lou had married a guy named Pipen and moved to Corpus Christi, Tex.

Back to the computer. Costa looks up Pipen, finds nothing. Tries a few other spellings, then clicks on Pippen. No phone listing, of course, but turning back to his unlisted-phone database, Costa gets a number. Doing a real property search, he confirms the number came out of Corpus Christi. Calls the guy; turns out he is indeed the husband; that Tami Lou has put herself through school and is now working for Apple Computer. She has been wondering about her father. End of story. Tears flow at a reunion. Costa is a star.

So it goes. That's the kind of thing Costa does regularly. He's found people all over the map, where others, including the cops, have failed. For a murder trial involving four gold miners, Costa tracked down a witness who'd fled to New York. L. J. went east to persuade her to testify. The witness returned, springing one of the accused. For a woman divorcing her husband, a shyster who claimed he was broke, Costa tracked property records that showed the lawyer was rolling in dough -- he owned an office building worth a cool $1 million. Law enforcement can do this, too, but it has to wade through the bureaucracy, obtaining court orders and a pat on the back from a judge. What it needs three months for, Costa can do in hours.

Back in Sonora, L. J. hands Costa a wad of phone messages and then says she's going outside for a smoke. He glances at the messages. A local attorney who needs help tracking down his client's old cell mate. A fellow P.I. trying to locate a deadbeat dad. Back to the grind. Costa shakes his head and turns to the computer. "Listen," he says. "You can beat the system. Just don't own any property, don't stay in one place, keep your yap shut, don't have credit, don't drive a car, don't keep a job, don't pay your taxes, and never, ever apply for a social security number. That way, I'll never find you."

Freelance writer Mark Wheeler ( lives in Canoga Park, Calif.