Who takes care of the kids? In the Washington metropolitan area, the nation's highest concentration of mothers who work, answers to that seemingly simple question are increasingly complex and often frustrating.

One Virginia mother became so desperate after six months of searching for a day-care arrangement for her 2 year old that she offered to buy her parents a car and send them on a cruise if they would relocate here and help care for the child.

A worried District man who had no wife, no children, not even a steady date, signed up on the waiting list of a prominent northwest D.C. day-care center known for infrequent openings. He was more optimistic about marriage and fatherhood than about finding good child care.

"I had a lovely woman taking care of my first baby at my home," recalls Kim Smith, 34. "The day I came home from the hospital with my second child, my child-care provider gave notice. I totally freaked out. I had to find someone else again. I wanted to throw her and myself in front of a speeding Metro bus." Smith calls the working parents' search for quality day care "probably one of the worst experiences."

She first faced those frustrations and fears two years ago when, as the nation's only female helicopter-industry journalist, she was pregnant with her first child and didn't know where to turn for advice.

Her colleagues were mostly male. Smith, who had been editing Rotor & Wing International magazine for the American Helicopter Society since 1975, knew only one friend who had given birth recently, a former society staffer who had gone on to administer the National Space Institute on Capital Hill. Smith started calling Susan Satterfield three times a day.

"Susan was the only person I knew whom I could pester about what I could do." Smith says. "When I got pregnant, I realized I had thousands of questions . . . How much does child birth cost? Should I have the tests done? Which hospital do I choose? How do I select day care?

"I kept bothering poor Susan. Then I decided I was basing answers to all these important questions on information from one person," says Smith. As a writer and editor, it wasn't the way she conducted business. She began looking for local resources. "They were out there but they were very disparate," she says. "There just wasn't any information and local references that pulled it all together. That's when we said, 'Ah-ha! We'll do it.'"

Armed with personal computers, Smith and Satterfield started organizing a data bank -- up-to-date resource information for the area's working mothers. Leaving their other jobs behind, they moved their upstart operation, Metropolitan Mothers at Work Inc., into a cramped Bethesda office and, through word of mouth, the news soon spread.

"Little notes about us appeared on the YWCA bulletin boards," says Smith. "We got deluged with calls. Here we were answering all these questions and we hadn't even made a policy about charging for our service."

They agreed a book was the answer, with low-priced monthly seminars covering pregnancy through child care.

"Since we're both writers the solution was obvious," says Satterfield, 30. "We decided to create a comprehensive directory for working moms." But Smith and Satterfield decided unless they could come up with enough money beforehand to underwrite a 10,000 book press run, they wouldn't do it.

"Everybody laughed at us and said, 'There's no way,' " says Smith. "We found a local distributor and took in about $27,000 in advertising in one month, without a product, without a contract, on a handshake and a smile."

Using a survey based on the 30 most frequently asked questions by some 500 parents they polled on child-care issues, Smith and Satterfield profiled 422 Washington-area child-care facilities. They researched book chapters on the "Rights of Working Mothers," "Childbirth Options," "Budgeting for Your Baby," "Choosing a Pediatrician," and "Options for Infants," among others. They charted the facilities, costs and attitudes of nine area hospitals on child birth. They catalogued services, agencies and products available here for infants and children.

Between the two of them, over the 18 months from the conception of the resource center to the publication of the 512-page Metropolitan Mothers at Work Book ($8.95), Smith and Satterfield had or conceived four children. They experienced a 45-minute, unmedicated birth and a 20-hour labor climaxing in an emergency Caesarean. They tried six different child-care arrangements, endured debilitating morning sickness and suffered two miscarriages.

Reflecting the "crisis in child care in this area," says Smith, book sales have been brisk and panicky calls to the office average 20 a day.

Finding proper infant and child care seems to be an insurmountable task for many new parents, say Smith and Satterfield. Openings at many of the licensed and better known child-care centers are often filled, and the more than 75 percent of child-care facilities and homes in the area that operate without a license rarely advertise their services and aren't easy to locate.

Smith recalls a woman who recently called in tears. She worked at Children's Hospital and, since having her baby, had been away from work for three of the allotted four months leave. "She thought that four months to find child care would be enough, but it wasn't," says Smith. "She had one month to go and was pulling out her hair. She had called every single listing in Montgomery County that provided infant care. She couldn't find anything and she was petrified."

Smith coached her over the telephone on how to write a classified ad that would attract response. "If you write a newspaper ad that's filled with 'musts' -- must be nonsmoking, must speak English, must have own transportation, must have child-care experience, must have references -- you're limiting your possibilities.

"Rather, write 'warm, loving environment, care for three month old, bus line, salary negotiable, perfect English not required.' She called me a week later, totally ecstatic. She had gotten 200 responses from the ad. She interviewed 20 people and had her pick of 10.

Smith, who pays about $150 a week for a 20-year-old woman to care for her baby at her home, says the cost of child care catches most first-time parents by surprise: "Most people don't realize the expense of it. They look at the cost of the formula, equipment, diapers -- but they forget about the child care.

"It is a lot of money. It is the fourth biggest expense of any household -- housing, food, taxes and child care. We counsel thousands of mothers who call us up lamenting the cost of their child care. But when you add it up, it isn't that much to pay for the child who is the most important person in your life."

For more information on Metropolitan Mothers at Work Inc., (301) 986-0725.