IT OFTEN HAPPENS this time of year as you wander

among the golden trees and feel the autumn chill in the air. Suddenly, after years of toying with the idea, you realize that you finally have the time and money to indulge in one of America's most enduring mythical yearnings--to build your own log cabin way the hell back in the woods somewhere.

The urge is not confined to kooks or faddists. Housing industry experts estimate that there are nearly 1 million log buildings in the United States today, with up to 50,000 new structures being added each year.

Surprisingly, the federal government, not often noted for its spirit of romance, is the largest owner of log buildings, in many of the nation's national parks, on military bases and other federal properties. Likewise, many state governments require log buildings in the parks and reserves they maintain. And, of course, the presidential retreat at Camp David in the Maryland hills west of Washington is completely constructed of logs.

The problem then for the modern dreamer of log cabins is not to invent the wheel again, but rather to utilize intelligently the considerable information and services already available.

For those in a hurry, and who have money to burn, it's a simple matter of signing over a check to one of the many commercial log house builders who operate from Maine to Oregon, from Georgia to Alaska. One day a flatbed truck shows up and dumps off what appears to be a child's puzzle in log form, then hired workmen erect the structure in a day or two and your sparkling new house is ready to show. These prefabs can cost as little as $20,000 or better than $100,000. (In 1980, the average new commercial log house sold for $67,000, excluding land, wiring, plumbing and other expenses, reports the Log Home Council, an industry trade group.) Loretta Lynn's parents live in a commercially built log house in Nashville that cost more than $300,000 and boasts every modern convenience imaginable.

The trouble for us dreamers is that buying one of these ready-made Tinker Toys has precious little in common with the American woodsman's experience of clearing the forest and building a house in the wilderness with muscle, sinew and a broad sharp axe. There is, after all, something redeeming and authentic about working with your own hands--and the hands of your spouse and kids, for that matter--to make real your cherished dreams. For many people, to buy a prefab log cabin profanes the very reason for having it. Why not buy a high-rise condo instead and save yourself the trouble?

For those souls who want to consider doing all or part of the physical work in building an authentic log cabin or house, the best advice in the world is to head for the nearest bookstore or library. In the past decade more than 50 new books and reprints of old standards have been published on log construction. But like everything else in life, the value here varies considerably. Some of the books are the work of zonked-out counterculture types whose own log cabins haven't lasted more than two seasons. Then there are ponderous academic tomes by engineers and scientists so abstruse and boring you'll have to stand in the rain to avoid falling asleep while reading them.

Fortunately, among this mass of information several works stand out. Lest you think log-cabin building is a dream to which only a he-man is susceptible, you should try to find Anne LaBastille's timeless Woodswoman, (Dutton, $10.95; paperback, $4.50, 1978). It is perhaps the best-written portrait of the psychological lure simple rustic living in a log house has on the modern person.

Alex Bealer and John Ellis' exquisite The Log Cabin (Crown $17.95; paperback, $8.95, 1978) is a reader's and dreamer's book, a finely crafted journey in pictures through all the classic log cabin styles worth seeing in North America. There is plenty of commentary and good advice to would-be builders, but the photos alone are enough to let you know the breadth and depth of log house construction possibilities. The Complete Log House Book, (McGraw-Hill; paperback, $9.95, 1979) by Richard Skinulis and Dale Mann, is a complete summary of the craft of log- house making, including diagrams and photos. Between the two of these books you'll have a very good idea of what your log cabin or house can look like and some of the things you'll need to know to buy it or do it yourself.

Both of these works delight the eye and the imagination, but they are short on the how-to aspect of log building. There just isn't enough detail and practical advice to stake your future comfort and safety on these books.

Far more detailed and informative is a just-completed three-part series of books by Charles McRaven, one of the genre's historians and a teacher of the craft to students from Canada to Missouri. McRaven, who has a PhD in journalism, not only provides a no-nonsense guide to building a log house, but his writing is easy to digest, anecdotal and full of tips on how to reduce cost, save your aching back and beat the contractors at their own game. Moreover, McRaven is an exponent of the hewn log cabin, as opposed to the round log cabin, and provides a marvelous history of log-cabin making in this country to support his contention that hewn logs are better.

Whatever the merits of that argument, McRaven's work is something to buy and carefully consider before you actually start your log cabin. His advice on lot location, cabin styles, water and sewer problems, foundation worries, right on up through the house to the chimney, are worth their weight in gold. These are books to put on your library shelf, if for no other reason than as a hedge against a future depression or war. With them you'll never fear for housing.

The titles of McRaven's delightful trilogy are: Building the Hewn Log House, (1978), Building With Stone, (1980), and Country Blacksmithing, (1981) (Harper & Row; each $14.95; paperback, $8.95).

Another standout title is Vic Jansen's new Your Log Cabin (Muir Publishing, Garden Vale, Quebec, Canada H9X 1BO; paperback, $12) which is marvelously effective because it assumes that the reader is from another planet. Jansen lays out plans and takes you step by intricate step through the entire process in a way only the illiterate could fail to understand. His work is also written so that you cannot proceed to the next chapter's work without having mastered that which comes before it, a sure-fired cure for impatience.

Jansen's publisher also sells The Log Home Guide, a glossy magazine containing a wealth of information the potential log buyer or builder needs. The guide covers the latest breakthroughs in technology and technique, new manufacturers; lists the dozen or so log building schools which offer the neophyte hands-on training in log cabin cutting; and covers of the regulatory beat. (Cover price varies; write Log Home Guide, Box 37, West Rutland, Vt. 05777).

If all of this guidance assaults the image of log cabin building as being a contest between forest and man, or forest and woman, consider--at least one benefit of living in our information age is that with the accumulated knowledge in our books we don't have to make the same damned mistakes those pioneers did.