Wanted by the FBI: your help. Along with high-tech tools, it relies on `He went that-a-way!'

Tracking down fugitives in the United States has never been easy work. A century ago, it meant assembling a Wild West posse and racing off at top speed after a cloud of dust on the horizon.

Nowadays, even with the help of court-ordered wire taps, computerized files, and high-tech forensics that can lift fingerprints off pieces of paper, US marshals and other federal law-enforcement agents still rely on public-spirited citizens to point them in the right direction, if not yell ``He went that-a-way!''

``It is not like following footprints in the snow,'' says veteran FBI agent Kenneth Walton. ``Somebody has to tell us where the fugitive is or where he is going to be.''

Such tips have helped the Federal Bureau of Investigation nab roughly one-third of the 372 fugitives placed on the bureau's ``Ten Most Wanted'' list since its inception in 1950.

If it hadn't been for a telephone call to the FBI by one of his ``friends'' in Washington state, convicted spy Christopher Boyce might today be living quietly in Moscow. Instead, the prison escapee was captured at a Port Angeles hamburger joint by federal marshals on Aug. 21, 1981 and is now living securely behind bars at the Marion, Ill., federal penitentiary.

Other captures of fugitives, though, like the Wednesday arrest of alleged neo-Nazi Richard Scutari in San Antonio, come as a result of basic, dogged police work.

Mr. Scutari, reportedly a member of a neo-Nazi group called The Order, had been on the FBI's Ten Most Wanted list since September. He was sought in connection with a $3.6 million armored car robbery in Ukiah, Calif.

FBI agents had suspected Scutari was in Dallas and had held a press conference to publicize the case. But the break that led federal agents to the car-repair shop where Scutari was working was a routine search of records using aliases thought to be employed by the fugitive.

There is no magic formula for capturing fugitives, experts say. Officials at the Marshals Service and the FBI, the two federal agencies with primary authority to conduct national and international manhunts, say it is usually easier to solve a particular crime than to locate a cautious and crafty fugitive who knows he is being hunted.

At present, law-enforcement officials estimate that there are 237,000 fugitives from US justice. That is roughly the equivalent of having the entire population of Syracuse, N.Y., on the run. Among them are an assortment of modern-day desperadoes ranging from cop killers and bank robbers to low-level bail jumpers.

At present the FBI's Ten Most Wanted list has been narrowed by recent arrests to seven persons. They include two suspected narcotics dealers, a suspected organized-crime figure, a suspected bank robber, a suspected robber-kidnapper, and two men suspected of murdering police officers. The ``top ten'' are the fugitives the FBI deems to pose the most danger to society.

``We want to take the most violent criminals off the street as soon as possible,'' says Allen E. Meyer, chief of the FBI's fugitive unit.

Other notorious fugitives, such as Edward Lee Howard, a former Central Intelligence Agency employee suspected of having become a double agent for the Soviets, are not currently on the top-ten list because they don't have a long history of violent crime. Nonetheless, officials say, the Howard investigation remains a high-priority international manhunt. There have been reported sightings of the 34-year-old former Peace Corps worker in Mexico and Finland.

Howard has advantages over many fugitives. He was trained by the CIA in how to detect surveillance and how to elude agents trying to follow him. He is also said to speak fluent Spanish and Russian. According to an FBI flier on him, Howard is ``considered armed and dangerous.'' The flier says Howard may be traveling under one of several aliases, including Patrick M. Brian, Edward L. Houston, James Rogers, and Roger Shannon.

Some officials speculate that Howard may already be living in the Soviet Union. If true, it would not necessarily mean the end of the US manhunt.

Federal agents pursuing renegade intelligence agent and arms merchant Edwin Wilson knew he was living in Libya. ``We even had his telephone number. We would call him up and talk to him,'' says Howard Safir, associate director for operations at the US Marshals Service.

Since it was unlikely that Libyan leader Muammar Qaddafi would honor a US extradition request for Mr. Wilson, American law-enforcement officials had few options.

There were suggestions of a dramatic commando kidnapping, but investigators decided instead to play on Wilson's greed in an attempt to lure him out of Libya to a country where he would be more vulnerable to apprehension.

Wilson was duped into leaving Libya under a phony promise that he could set up a US-sanctioned arms business in the Dominican Republic. When he arrived in the Dominican Republic, local authorities refused to admit him to the country and placed him on the next plane to New York. He was arrested upon arrival at Kennedy Airport.

There are few rules when it comes to bringing in fugitives. ``Hit above the belt and three-minute rounds -- it isn't that way,'' explains Marshals Service Director Stanley E. Morris. ``If you can clip [a fugitive] with a rabbit punch or kick him to make an effective arrest, that is what you are going to do. Sneak punches are fair in this business.''

US courts have tended to agree with Mr. Morris's assessment. Federal judges, including Supreme Court justices, have ruled, in effect, that as long as American agents do not torture or physically abuse the fugitives they bring in, it matters little if the law enforcers use trickery or deception to nab their quarry.

Last fall, the US Marshals Service in Washington sent out 3,000 ``invitations'' to people wanted for various crimes, notifying them that they had won free tickets to a Washington Redskins football game. Almost 100 fugitives showed up at the District of Columbia Convention Center to partake of a free brunch and pick up the Redskins tickets.

It was a gala affair, for a while at least. One federal marshal was even dressed up in a huge chicken suit.

The newly arrested suspects never did see the game.