AS THE SAP BEGINS TO RUN, and the office walls close in, and you yearn to be captain of your soul . . . Well, they're waiting for you, over at the "How-to" shelf. A little above Jane Fonda's Workout Book, and just to the right of Plumbing Repairs Made Easy, the season's start-your-own business books are singing their siren songs. Some dig deeper than others, and not one of them is exactly fun to read (although some make the mistake of trying), but they bring into focus a whole world out there that a lot of us have been too bogged down to be aware of.

To lure you into the tent, they let you feast your eyes on the fun and money that other self-starters have found at the rainbow's end. The couple who so enjoyed their vacation barge trips to Europe that they formed their own barge company, and now float some 2,000 clients a season through Europe's inland waterways. and live in a Swiss castle off the proceeds. The man who runs a mail-order business in hard-to-find tools (and discovered it costs 10 times more to insure a package than to replace the tool). The couple in Bath, Maine, who teach people how to build their own houses; the young men who market windmills; the woman who started a catering business in her apartment . . . these happy few and dozens more, all beckoning to you to take the plunge.

The lost friends, broken marriages and red ink that turn these dreams into a living wage are only spelled out later in the course. So if the class will stop staring out the window and shuffling its feet, we will examine what the season holds in store.

Making It on Your Own, by Dr. S. Norman Feingold and Dr. Leonard G. Perlman (Acropolis Books, $12.50) looks from the outside as though it had been designed by the fellows who spray- paint the New York subways. The authors are psychologists and career counselors, and their quirky syntax in a dizzy display of large, small, bold and italic type faces reminds me of the home-printed pamphlets you pick up in a health-food store.

As your eyes dance down the page you learn that the authors aim to provide "a resource guide that you will be able to use to make other decisions not only about your business, but about yourself as well." Are you even sure you're the type to be in business for yourself? The authors open with a Small Business Personality Profile quiz to help you sort this out. (Are you a self-starter? How do you feel about people? Can you take responsibility?) Do not give up if you fail this test. There will be others. You will get a chance to ask yourself what kind of business you should start (with lists to jog your mind), and where. (Have you checked the traffic? The security? The sewer arrangements?) What customers are you aiming for? How much will it cost? How do you plan to keep the books? For homework, there are reading lists, and sample forms to fill out. For moral support, there are running comments from others who are safely launched, and interviews with successful entrepreneurs around Washington based on the authors' "Structured Interview Format Sheet."

Between exams, the authors spell out the various forms a business can take--partnership, proprietorship, corporation or franchise--and discuss what each has going for it. If you plan a family business, they suggest tactful ways to steer troublesome relatives away from the center of power.

Among the many wonders of the reference section, which takes up more than half of the book, are the texts of 24 of the Small Business Administration's 45 Selected Counseling Notes, which are supplied by various trade associations, and abound in home truths. ("The owner manager of a radio-television repair shop wears many hats." "A professional interior designer is one who is qualified by education and experience to identify, research, and creatively solve problems relative to the function and quality of man's proximate environment.")

You can also learn that the dry cleaning trade is now the "fabricare" industry, and if you dream of joining it, you should start reading Coin Launderer and Cleaner magazine. If you see yourself at the helm of a full-service car wash, you should sign up for Auto Laundry News and Self-Service Car Wash.

All in all, the number of small-business support systems you find in this book makes you realize that there is a whole subculture of public and private organizations devoted to the care and feeding of small businesspersons. All you have to do is find one willing to take your case.

For the full, mind-bending extent of the network, spend a long weekend with The Insider's Guide to Small Business Resources, by David E. Gumpert and Jeffry A. Timmons (Doubleday, $24.95). Gumpert, a former report for The Wall Street Journal, is now small business editor of the Harvard Business Review. Timmons is a professor of management at Northeastern University. Aided by a small but dedicated band of researchers, they have somehow subdued an untamed ocean of information and forced it into an orderly, cross- indexed march through 407 enlightening pages.

In chapter after chapter, list after list, they cover business resources all over the country, commenting on them as they go along. Before they get to business courses, they tell you that "Most entrepreneurs find it unbearable to sit and listen to theoretical lectures and discussions about hypothetical business problems." In the chapter on government funding you learn that, say, the National Science Foundation "makes the bulk of its research grants available to universities, and its officials are most comfortable dealing with universities." Its list of consultants who specialize in federal procurement outlines their professional background, what their specialties are, and how much they cost. The list of venture capital firms tells how much they're willing to lend, how much they expect to make from a deal, and how they like to be approached.

Sections in the appendix tell you, step by step, how to develop and use a business plan, and guide you through a typical venture-capital agreement. All in all, with no games or gimmicks, it is the most comprehensive and useful book on the shelf.

Its only close rival in awesome detail is The Partnership Book: How You (and a Friend) Can Legally Start Your Own Business, by attorneys Dennis Clifford and Ralph Warner (Addison-Wesley, $14.95), a blockbuster paperback that tells you almost more than you ought to know about getting into--and also out of--partnerships. To keep the class from going numb, the authors make frequent pauses in the legal details to recount the adventures of John and Sara, a fictional pair from Coeur D'Alene, Idaho, who enter a turbulent catering partnership to market their "chocolate moose."

Back in the mainstream, Robert Fierro's The New American Entrepreneur: How To Get off the Fast Track Into a Business of Your Own (Morrow, $13.50) comes at you with a disco beat that some of us aren't ready for too early in the morning. ("If you're a survivor, kid, you're an entrepreneur.") But behind his fancy packaging he makes a strong case for relentless homework; offers detailed and practical suggestions, and makes you realize that unless you put a realistic money value on every aspect of your business project, including your own time, you could sink without a trace before you start. "The only way to figure out how much money it will take to open the door," he offers cheerfully, "is to determine how much you expect to lose in the first three years." He reckons the figure for a first restaurant in a decent location could run to $1 million. So much for going public with your muffins.

Jerome Goldstein, author of In Business for Yourself (Scribner, $12.95), spent 25 years with a big publishing firm before he decided to start a magazine of his own--a bimonthly that focuses on "new businesses outside the mainstream of the economy." He breaks away from the standard patterns to explore the philosophical underpinnings of the unorthodox new businesses formed in recent years. He touches on the mechanics of a new enterprise, but his main goal is to pry your mind open to the potential that awaits outside the system--from sewage disposal and integrated pest management to wooden boat building, and other wonders of "appropriate technology" inspired by E.F. Schumacher's Small Is Beautiful, published in 1973. For Goldstein, the inner logic ("entrepreneurial ecology") that breathes life into a new business is more important that the formal business plan urged on you by most of the others in the field. Even some of the resources he mentions--the Briarpatch Network, a business bartering outfit in San Francisco, and the Center for Innovation in Butte, Montana --have an offbeat tilt to them.

The most intensive and demanding of the seminars is the one offered by Stanley E. Pratt and the editors of Venture Capital Journal: How to Raise Venture Capital (Scribners, $17.95). The 24 contributors are lawyers, venture capitalists, corporation executives, business school teachers, or a combination thereof, and together they cover the whole spectrum of that peculiarly American way of life.

The intricate financing arrangements that resemble the wiring diagram of your home computer are not for the beginner. But they brace you for what's in store if your new business takes off.

If you think you can give up and go back to the office after you finish this course, it's because you haven't read Getting Rich in Real Estate Partnerships (Warner, $12.95). Ten years ago author Ruth Baker Bricker figured that if she made $20,000 a year in 1970, she'd have to make $50,000 in 1980, and $134,000 in 1990, just to stay even. She found that real estate values "were among the few things that were going up faster than inflation," began investing in group real estate ventures, and is now on her way to her second million. By the time she's finished telling you how to pick good properties ("Buy the worst building in the best neighborhood"; "Find a property with the right things wrong with it"), and how to manipulate your funds to have more investing money than you thought you had, and how to manage properties for a profit once you've got them (wrap the pipes and solar heat the swimming pools), she makes you wonder if you can afford to go back to your old job.