"This year," announces Washington researcher Matthew Lesko, "the federal government is giving away $678 billion. That's the equivalent of $4,500 for every adult American.

"Everyone's talking about Reagan budget cuts. Well, there's more money being given out than ever before."

And although that news may be a surprise, it's hardly surprising that a lot of people are going after that government green. Lesko's book, Getting Yours: The Complete Guide to Government Money (Penguin Books, 346 pp., $5.95), has been on national best-seller lists several times since its publication earlier this year.

Information for the book, a compendium of about 800 sources of government loans, grants and direct payments, was drawn from an Office of Management and Budget (OMB) catalogue.

"I didn't believe it when I first saw it," admits Lesko, 39, who is the co-founder of Washington Researchers and a frequent lecturer on free government resources. He then went on to verify the information.

"The money," he says, "has to go to someone. Particularly now, with hard times, I think more people should be aware of the kinds of federal assistance available."

The same people who get the money every year "know about the programs and they keep applying. The ones who don't get it are the ones who always think federal money is for someone else. Well, it's our money," he proselytizes. "The government got it from us in the first place."

Lesko says more than 500 of the programs are open to individuals. (Also eligible are nonprofit organizations, private firms and institutions, local and state governments.)

"Despite what you see in the media, there is more money available for education than ever," he claims. "A couple of the programs have been cut out, and the requirements on others changed, but the money's there."

For example, "There's a Smithsonian program that pays graduate students up to $14,000 a year. There are more than 60 programs aimed at higher education, more than 100 programs for people who want to start a business or improve their business. The Small Business Administration will provide loans to start 20,000 new businesses this year.

"Right here in Washington," notes Lesko, "a neighborhood in Northeast had a rat problem. Around 70 percent of their homes were infested with rats. What they did was find a Health and Human Services program for urban rat control. It was for local government.

"Well, they told the city government about it, and they got a $1.2 million grant and reduced the infestation rate to 4 percent."

While Lesko is convinced the money is there for the taking, "Once you have identified the program or programs that can help you, your work has just begun. Now you have to get the money."

He stresses, however, that "there is no mystery in the method. You do not need a Ph.D. or a Washington office. All you need is patience, determination and hard work, if you are eligible."

Lesko's research and consulting firm specializes in providing information on federal government resources to business clients. ("Most of them Fortune 500 companies.")

"The funny thing about it is we use Washington like our own in-house library. Most of the time we get the information for free . . . We charge our clients around $75 an hour to get stuff that we get for free. They actually pay twice: once with their tax dollars and again when they pay us."

And for anyone who wants to do their own research on getting theirs, the information in Lesko's book is in the OMB's "Catalog of Federal Domestic Assistance," $30, available from the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402, or by calling (202) 783-3238.)