Long lines form every few weeks inside the headquarters of the Watts Labor Community Action Committee, filled with grim faces in search of work, wondering if all the talk they hear of a booming economy is just a joke.

"Give yourself a hand for showing up today," George Alexander, a jobs coordinator at the center, told one gathering recently as it filed into a dimly lit auditorium and slumped into folding chairs. There was only faint applause, for the group seemed to sense the bad news he had to deliver.

"But I have to warn you up front, some of you may not be employable."

That hard truth still abounds here on the scarred streets of Watts, one of the poorest parts of Southern California and for generations a prime destination for migrants -- first waves of blacks from the deep South and now Mexicans and Central Americans -- striving to get their first taste of prosperity.

Even now, seven years after riots and a recession devastated the area, and with much of the region in robust economic health, Watts and its neighboring communities across the vast tracts of South Central Los Angeles are still struggling. And their troubles in many ways illustrate how difficult it remains for the urban poor to reap benefits from the nation's surging economic growth.

"You definitely won't find any economic boom around here," said Tim Watkins, a director at the Watts center, which is a hub for social services and cultural activities in the area. "We're all just scrambling for the crumbs from it."

Unemployment is as low as it has been in a decade in metropolitan Los Angeles, and the rate of business expansion is so great it is pulling many more disadvantaged job seekers into the work force. Nationally, unemployment among African Americans and Hispanics is hitting record lows. But in Watts and urban communities like it across the country, where unemployment is still nearly twice the national average, those signs of progress are hard to see -- not with empty and weed-filled lots standing in wait for promised retail development, already years late, manufacturers leaving for cheaper labor markets and job-training fairs as busy as those held here twice a month.

Some problems that residents have finding work are of their own making, such as bouts with crime, drug abuse or reluctance to prepare better for changes in the job market. There is little question, though, that the area, like many other poor urban communities, is also a victim of substantial fear and neglect.

Enticing developers to launch large commercial ventures in South Central remains difficult and public transportation is abysmal, leaving many residents isolated from the thriving job centers in this sprawling region. The county bus system is so poorly managed -- it is under a court order to improve -- that community activists have staged fare strikes in the past year to protest overcrowding and delays. Some employers apparently are hesitant to hire residents who have to rely on the buses to get to work.

"They tell me those people are not desirable hires," said Amador Diaz, who runs another local work force center, "because buses here are never on time."

The wounds across South Central from rioting in 1992 also still cut deep. More than 9,000 businesses in the area, which is now home to as many Hispanics as blacks, were destroyed or damaged in the nights of rage that followed the acquittal of a group of white police officers who were accused of beating black motorist Rodney King. Some 6,000 jobs were lost.

Many of those small businesses have never reopened. Others will not even consider coming. Unemployment in Watts, which also never fully recovered from rioting in 1965, is twice the overall rate for Los Angeles County.

And the few jobs that community organizers manage to find for residents often seem to be little more than low-paying scraps -- temporary construction or carpentry work, night security posts, or entry positions in food service.

"I don't know where the jobs are," said Jesse Brew, 37, who was laid off months ago from an auto parts store that was cutting jobs. He left the Watts center the other day with no offers and little hope. "I would drive a truck. I would work in a warehouse. But you can't find it. It's a cold thing, man," he said.

"I would be willing to try almost anything," said Kimya Williams, 26, who also came to the center looking for work. "But none of my calls get returned."

President Clinton rolled through Watts earlier this summer to spotlight the need for more jobs during his whirlwind anti-poverty tour across the country. But even some of his ardent supporters here say they doubt that much progress will come from his short visit until more attention is paid to a chronic and fundamental problem. A sizable part of the potential work force in the community lacks the technical skills to compete for the kind of jobs the new economy is creating.

The Watts community center is trying to train some local residents in computer use and to direct others to privately run programs, but its resources are stretched thin. Community leaders say what they really need is for more of the employers that are coming to the area to make hiring local residents a priority, and then be willing to train them on their own dime if necessary. "We need more employers to take a chance," said Alton Blake, who supervises job services at the Watts center. "It's the only way things will change."

Not every sign is bleak in South Central Los Angeles, however. A $40 million shopping mall projected to bring about 500 jobs to the area is scheduled to open late next year about 10 miles from Watts. It is the largest commercial development of its kind here in more than a decade. Long-needed supermarkets and a few national retailers are also on the way. A hundred stores that sold liquor were torched during the riots and have not reopened, which is welcome news for many civic leaders, who viewed them as a scourge.

Local officials hope a federal plan that will offer large tax breaks next year to companies that open for business in the area -- now designated as an federal "empowerment zone" -- will help spur development.

But even that opportunity is coming late. Federal officials passed over Los Angeles the first time they awarded a cluster of needy cities the tax break package four years ago. And community leaders say it will not do much good unless the businesses that take advantage of the deal hire many local residents.

"There are a few signs that things could get better," said Fernando Guerra, the director of the Center for the Study of Los Angeles at Loyola Marymount University. "But it's a relative term. The area still has a long way to go."

Some analysts say companies are overlooking profitable opportunities in South Central. The area is large geographically and densely populated with miles of small single-family homes. Even though more than one-third of Watts residents, for example, live in poverty, there are many thousands of residents with disposable income who have a hard time spending it in their own neighborhoods.

"It has all the ingredients for some success," said Chris Hammond, a developer in the area. "But there's a big fear. People still think about the riots and worry about crime. No one wants to be the first in an area. We've really had to hold the hands of the businesses that have decided to come."

At the Watts center, no strategy is too small to try to get more residents into the growing job market. Thelma Cole, an administrator, organizes sessions that show job seekers how to create resumes, how to present themselves for interviews and how to find employers for whom they could be suited to work. The center even has a fund to help some residents pay bus fares to their jobs.

Cole reads every day how the stock market keeps rising, then meets with clients who keep returning to the community center with no new prospects.

"The jobs aren't here," she said.

Near the end of one employment workshop the other day, Chuck Radley, a man in his early twenties, said he had been looking for months for a job with no luck. He was standing in line with a dozen other black and Hispanic residents, young and old, waiting to speak to a representative from a snack food company.

"It just doesn't seem like there's much out there to find, even when you have some training and haven't been in any trouble," he said. "I've been looking for a long time, but I'm going to stay with it. One thing everyone needs is a job. If I don't find one today, maybe it will be next time."