Camarillo, Calif. — This must be the T-shirt capital of the world. Reading them is almost a full-time occupation. There are the geographical (''Shawnee,'' ''New Zealand''), the sporting (''Property of the Los Angeles Dodgers''), the plaintive (''I'm just a prisoner of love''), the offbeat (''This is my lay-about-the-house-and-do-absolutely-nothing T-shirt''), or the deprecatory (''Cherokee, Iowa, is not the end of the world . . . but you can see it from there.'')
For someone who lives in Europe and is returning after 20 years, this is also an eye-opening cornucopia of:
* Restaurants (even if the desire to cater to all tastes does tend to produce places with names such as Pancho Wong).
* The car as a way of life, a status symbol, a living room, and a statement of identity. Where else can a cheerful gas station attendant regale you with details of her new car, which just happens to be a $17,000, fire-engine-red Chevy Camaro convertible with a stick shift, a hood like the front end of a shark, and enough power to light up a subdivision?
* Elegant shopping malls: soft music in the air, twinkly little lights in trees, and bushes in central walkways - plus August advertisements for Thanksgiving and Christmas.
* Freeways whose distances are measured in time rather than mileage. (When we asked how far another town was, the answer was never ''60 miles'' or ''30 miles, '' but ''an hour'' or ''30 minutes.'')
* The odd, arresting sight: A large stone head-and-shoulders statue outside a Redondo Beach hairdresser's sported vivid green hair. On closer inspection the ''hair'' turned out to be luxuriant plants and grasses.
Then there was the Chevrolet sedan of 1950s vintage that turned into a beach parking lot north of Los Angeles at about 25 m.p.h. with 40 to 50 seagulls riding happily on its hood and roof. The bearded driver glanced at me . . . and nonchalantly tossed another handful of bread crumbs onto the hood as he drove on.
All this is a part of the world of particular interest to Europeans who live in older, colder, and more conservative places.
Just as California is where Eastern and Midwestern Americans go to find the latest in life styles, the question for Europe is whether California is also the vision of the future for other parts of the Western world.
Is the private automobile going to dominate Western Europe as it is already swamping tiny Britain? Are US-style supermarkets going to drive out completely the local specialty shop? How much is the computer revolution going to create more time for recreation?
California is either the end or the beginning of the United States mainland, depending on one's point of view. It is the apogee, or the nadir, of the American way.
It is the edge of Asia (most of whose population seemed to be at Disneyland the day we were there). It is a vision that some Europeans want to copy for its easy efficiency and high technology - and whose restless newness, materiality, and lack of roots many more hope to avoid.
New houses spring up like mushrooms as Americans keep arriving from other states, even though 14 percent interest rates have slowed the pace since May.
According to the California Association of Realtors, the jump from 12 to 14 percent in mortgage interest rates means a buyer needs $5,760 more in yearly income to qualify for a $115,000 home - and that's just the median price.
''Over the long term,'' said one stockbroker, ''the outlook is for more and more growth from San Diego to Santa Barbara, just as the East Coast is built up between Boston and Washington.''
Take Camarillo, a city of 40,000 people roughly halfway between Los Angeles and Santa Barbara.
Many of those people drive more than 100 grueling miles a day, round trip, to their jobs in Los Angeles. Yet the Camarillo city council has just approved another 144-unit hillside-housing development (over the loud objections of neighbors that the new houses would lower the water pressure, drive out birds and other wildlife, and lead to soil erosion and pollution).
While interest rates stay high, the housing boom will slow. But no one is predicting an end to the mushroom growth of places like Camarillo, with its backdrop of the Santa Monica mountains; its sunny year-round climate; its lemon groves and spacious, easy shopping.
California produces $14 billion worth of tomatoes, lettuce, cantaloupes - and dozens of other varieties a year. Once mainly Mexicans stooped in the fields, many of them illegal immigrants working for bedrock hourly rates.
Now, refugees from Vietnam, Laos, and Kampuchea are looking for work. So are newly out-of-work arrivals from the Midwest. So are unemployed whites from California cities.
Still, the number of farm jobs is falling. Growers complain about the provisions of the state agricultural labor relations board set up by former Gov. Edmund G. (Jerry) Brown Jr. (D) at the urging of United Farm Workers union chief Cesar Chavez.
However, we saw no signs of the new breed of gleaners being reported elsewhere in the state and in other states as well.
According to news reports, a growing number of Americans who don't qualify for government food aid have turned to gleaning fruit and vegetables from fields or sorting through rejected crops. One group in the state of Washington bases its efforts on the injunction to Moses in Leviticus 19:9-10 to leave the corners of fields and the gleanings of the harvest for ''the poor and stranger.''
Around Camarillo, however, machines would reap one day and plow under the stubble almost on the next.
Meanwhile, there are many other things to think about.
Accustomed to standing in line in British supermarkets, where you bring your own shopping bags and fill them at the checkout counter yourself, we marveled at the speed of California food shopping.
At Mission Oaks Plaza in Camarillo, the checkout clerk at Von's Supermarket passed each item swiftly across a beam of light shining up through the countertop. The light ''read'' electronic coded markings on each item. An itemized bill clicked out. She dispensed change from a tiny drawer, another girl packed the items into large brown bags, and we were on our way almost before we could blink.
''Soon there won't be anyone standing here at all,'' laughed the girl. ''It'll all be computers.''
Another major discovery was Mexican food - or at least the milder, mass-marketed forms of it: the taco, the burrito, the tostada. Particularly welcome were the sugary cinnamon flakes served as dessert at the Taco Bell chain.
Our children pronounced themselves satisfied with their first visit to Disneyland, in Anaheim.
The long day among the crowds and rides, the relentless cheerfulness, and the assault on the senses also had something for their parents: the appearance on a stage beside us of one of the giants of US jazz music over the past 40 years, Lionel Hampton.
To paraphrase the T-shirt: Southern California is not the whole future, but can you see it from here?