"What will they think of next?" the middle-aged woman sighed to nobody in particular.

She was standing in the middle of a jammed parking lot at a restaurant-gasoline station rest area on the main highway across East Germany. Her shopping bag was stuffed with French brandy. Swiss chocolate, and several pounds of West German coffee.

She had stood in line for eight hours to get these items at an "Intershop" in the restaurant building. The Intershops are places where East Germans who are in possession of West German marks, dollars or other Western currency that is called "real money" here can buy luxury Western goods.

The system has operated for years. But on Monday, April 18, new rules go ito effect that people here don't trust.

So all over East Germany, in all 200 places where there are Intershops, there are huge lines of people-more annoyed, confused and suspicious than angry-engaging in what could be called panic buying.

As of Monday, Germans who have Western money can no longer use it directly to buy at these shops. They must first go to a bank and turn it in for "coupons" in the same amount as the currency.They can then buy at the Intershops using the coupons instead of cash.

The coupons are supposed to be nontransferable, meaning they can't be passed on to another person.

In a related move increasing an a lready restrictive atmosphere here, the East German government has imposed new curbs on foreign journalists. The new regulations bar all but officially approved interviews and require journalists to submit in advance detailed information on all travel.

Although East Germany has signed the 1975 Helsinki accord pledging to improve working conditions of journalists, it traditionally had maintained restrictions more extensive than any other East European country.

Among other things, the standard practice here is that each visiting journalist must hire an official escort for $60 a day.

While the new restrictions on journalists are clearly designed to reduce the flow of news out of East Germany, the new currency regulation is based on more complex grounds.

Officially, the Communists Party says it is meant to stop a black market in Western currency, which draws about four or five times the official rate of exchange.

It is also aimed at the growing demand of East German repairmen or salesmen to be paid in West German marks for privately-arranged work done to get a house painted or a car repaired or a spare part in less than the many months that it would normally take.

There may also be political factors behind the new policy. Several Soviet Bloc countries have systems like the East German Intershops, but the East German system is far bigger primarily because access to Western money-mostly from relatives in Western Germany-is so much greater.

It is unofficialy estimated that these shops do over $1 billion a year in business, earn a profit of a few hundred million dollars for the government and gather all the hard currency in the country into government coffers where it is needed to pay off debts to the West and to continue importing badly needed technology and raw materials.

The problem, however, is that the system is so widespread that it had created a two-level economy in East Germany, divided people into haves and have-nots and embittered those in the latter category, which in many cases includes party workers who are forbidden contact with Westerners.

East German party chief Erich Honecker last year acknowledged that the system was not exactly consistent with socialism and started an additional system of shops where some of the same goods could be bought for East German money but at greatly inflated prices.

It is therefore felt that some of the pressure for the current move came from Moscow, which is aware of the concern in other East Bloc states over the easy availability of Western money in East Germany. It is also viewed as an attempt to at least appear to be doing something to make it look as though Honecker is trying to cleanse his socialist system of this Western intruder.

The key measurement of how real a change the new policy will be, however, will come after it goes into effect. What people are not sure of now is whether they will have to identify themselves to the bank authorities and whether they will be subject to questioning about where they got the money.

If they can get the coupons without such interrogation, then many people here seem to think that nothing really will have changed except that instead of a two-tier economy, East Germany will have a three-tier economy.

Early reports from East Germans who went to banks to buy coupons beforre the new law goes into effect said they didn't have to sign them or show identification. But the mood in the lines at the Intershops here is one of suspicion. Nobody seems certain that leniency will continue.