THE SUMMER Olympic Games in Los Angeles are more than a year away, July 28, to Aug. 12, 1984, but sports fans who want to attend the big events should start thinking now about tickets and accommodations.

Within a few weeks, the Los Angeles Olympic Organizing Committee will announce the nationwide distribution (probably through a department store chain) of mail-order forms for tickets. And already, international travel firms are booking large blocks of rooms in major hotels.

Because of the expected demand for tickets to such popular events as the colorful opening and closing ceremonies and the finals in gymnastics, cycling, swimming, diving and other sports, a random drawing will be held once order forms have been returned. Other tickets will be sold on a first-come, first-served basis.

During the games, 21 competitive and two demonstration sports (baseball and tennis) will be represented. With preliminary matches included, there will be about 352 different events, to which about 7 million tickets will be available for sale. The average ticket price will be $18, though 3 million tickets will sell for $10 or less.

Because Los Angeles is a major tourist destination, visitors should be able to find a place to stay during the Olympics, says Bill Arey of the Greater Los Angeles Visitors and Convention Bureau. But it may take some searching; so far, there are no plans for a central reservation service. In addition to travel firms snapping up accommodations for foreign visitors, the Olympic committee itself already has reserved 20,000 rooms in 51 of the city's major hotels for officials, the media and other members of the "Olympic Family."

To help other travelers find a place to stay, the visitors bureau is periodically polling its member hotels and motels to find out which ones still have rooms, and that list is available from the bureau. There is also a list of bed-and-breakfast establishments as well as a list of firms that are renting houses and apartments only during the Olympics.

Because the games will take place at 20 sites in the Los Angeles area, some as much as an hour's drive apart on the city's freeway network, one suggestion is to consider booking a room convenient to the sports that particularly interest you.

For more information:

Greater Los Angeles Visitors and Convention Bureau, 505 S. Flower, Los Angeles, Calif. 90071; (213) 488-9100.

Los Angeles Olympic Organizing Committee, Los Angeles, Calif. 90084; (213) 209-1984.

PREAKNESS PREVIEW: This is a tour for night people, a dusk-to-dawn exploration of Baltimore's historic sites that ends with a buffet breakfast at Pimlico and a chance to watch trainers and jockeys prepare the horses for the races, perhaps even for the Preakness a week later.

This is the fourth year for Baltimore Rent-a-Tour's "Preakness Insomniac Tour," which departs by bus from the Inner Harbor at 1:30 a.m. (yes, that's a.m.) on Saturday, May 14, returning at about 6 a.m. The streets may be dark, but you are not fighting tourist throngs.

Stops include the historic USF Constellation, the oldest American warship continuously afloat; the graveyard where Edgar Allan Poe is buried; Fort McHenry; Muhly's Bakery (you may get flour on your clothing, says a spokeswoman, but you can carry away a sample hot from the oven); and the Wholesale Fish Market (these folks get up early, too).

A guide accompanies the tour and, at the Pimlico clubhouse, will be available to identify the horses and explain what's happening on the track during morning workouts. The fee is $28 per person.

For information and reservations: Baltimore Rent-a-Tour, 3414 Philips Dr., Baltimore, Md. 21208; (301) 653-2998.

LEAD A LLAMA: For centuries, woolly llamas have been the beasts of burden in the South American Andes. For the past two years, they have been toting food and camping equipment into the Northern California wilderness on three-day "Lead-a-Llama Pack Trips" for outfitters Ken and Sharon Hansgen.

Unlike mules or horses, the llamas are "easy on the terrain because of their soft, padded feet," say the Hansgens. They are also "gentle, intelligent and very inquisitive." They can carry up to 80 pounds each.

On weekends from May to October, Ken Hansgen, a naturalist and biologist, escorts groups of eight people and five llamas on "leisurely" hikes, averaging about six miles a day. Children and senior citizens are welcome. Two nights are spent sleeping in tents or under the stars at a base camp, usually near a stream or lake.

In the early season, the trips go into the historic Gold Country of the Sierra Nevada foothills; as the weather warms, they climb to mountain elevations near Lake Tahoe; in the fall, they venture along the Pacific Coast at Point Reyes National Seashore.

The price of $60 per day per person includes most gear and all meals, which, says the couple, feature "California's agricultural products." The tour group meets at the head of the trail or another prearranged place.

For information: Sierra Llamas, P.O. Box 509, Loomis, Calif. 95650; (916) 652-0702.

CHEF'S FEAST: A tour with the stomach in mind, this eight-day gourmet excursion features meals prepared by three of Europe's noted chefs.

Two are from France: Alain Chapel, described by France's famous food critics Henri Gault and Christian Millau as "a really great cook," and Bernard Loiseau, whom they call "one of the most gifted chefs of his generation."

The third is Swiss, Fredy Girardet. New York travel agent Annemarie Victory considers it a personal coup to have been able to add this renowned chef to her roster. Somewhat reclusive, she says, he has turned down many such offers to cook or teach. But she knows him, so "I decided to ask him to design a meal for my special tour. To my surprise, he said yes."

Girardet will prepare a five-course lunch on the tour's sixth day, explain his recipes and select the wines. Dinner on Day 3 is at Loiseau's Co te D'Or restaurant in the town of Saulieu. On Day 4, both dinner and lodging will be at Chapel's auberge in Mionnay.

Other highlights include a Tattinger Champagne reception at the Hotel Crillon in Paris and visits to several wine regions with tasting tours at famed wine cellars. Accommodations, says Victory, are at "some of the finest hotels in Europe."

Land fare is $2,900 per person (limited to 15 persons per tour), with departures June 4, June 11, Sept. 16 and Sept. 23.

For information: Annemarie Victory, Tamas International Travel, Inc., 15 E. 26th St., New York, N.Y. 10010; (212) 725-1111.

SPRING BLOSSOMS: Down in Charlottesville, the garden club has designed a Friendly Gardens walking tour, visiting the kind of small, simple backyard gardens that practically anybody could go home and duplicate. Aimed at the beginning gardener in search of ideas, the display of blossoms and plants is part of Virginia's week-long garden and homes tour (April 23 through May 1), now in its 50th year.

In 35 areas of the state, garden clubs are sponsoring tours of 226 homes and gardens and 50 historic landmarks. Proceeds from the Historic Garden Weeks help landscape the gardens and grounds of 32 of these landmarks. Last year's tour drew an estimated 40,000 visitors, including busloads of gardening buffs from outside Virginia.

Throughout the week, there will be candlelight tours, gourmet suppers, cocktail receptions and box-lunch picnics as a part of a visit to a Hunt Country estate, the historic plantations on the James River near Williamsburg or a cottage by the coast. Many of the homes and gardens are open only during garden week.

Because the tours in each area are scheduled at varying times during the week, the best way to begin is to obtain the 164-page guidebook, available free from the Historic Garden Week Headquarters in Richmond, many offices of the American Automobile Association and the Chamber of Commerce of the area you are interested in visiting. The Friendly Gardens tour in Charlottesville will be open April 24 from 1 to 5 p.m. and April 25, 10 a.m. to 5 p.m.

Tour prices also vary, but expect to pay about $10 per person to visit five to eight homes and gardens in one area, usually including some type of refreshments ($6 for seven gardens in Charlottesville). Some flower fans take a different tour each of the nine days of garden week, says spokeswoman Charlotte Massie; others pick one or two for a weekend, visiting a different part of the state each year. "Even if you travel like the wind, you couldn't go to all of them in a week."

To obtain a guide by mail, write: Historic Garden Week Headquarters, 12 E. Franklin St., Richmond, Va. 23219. Enclose $1 for postage.