Whenever White House press secretary James S. Brady stepped to the podium to give the daily briefing for reporters last week there was a scattering of applause and cheering.

"You're going to write a piece about Brady?" joked one White House official. "You must be an investigative reporter."

The applause and cheers were sarcastic and the joke, which not everyone found funny, was that Brady had become a difficult man to track down in the first weeks of the Reagan administration.

It was a peculiar twist. When Brady was named to the job he was known to reporters who covered the Reagan campaign and the transition as a spokesman who made great efforts to get answers to questions and be available when needed. The only rap against Brady was that since he was not a longtime Reagan loyalist he might not have enough access to the president to be able know and communicate the pesident's thinking.

Instead, Brady's access to Reagan has been ample. What has been lacking is reporters access' to Brady.

The Brady-run press office hit the ground running. The inaugural and events connected with the hostages' return were well handled, a random calls himself by his nickname "The Bear."

He sent his deputies, Larry Speakes and Karna Small, to handle the daily briefings and he was rarely in his office to talk with reporters or return reporters' telephone calls.

Brady was spending his time with Reagan.

"You have to front-end load this," Brady said in response to criticism of his performance. His first priority, he said, had to be to get to know the president better by observing him in all sorts of situations.

"It's working itself out now," he added.

Brady did seem to be resurfacing. He gave three of the five briefings last week, compared to only one the week before. He was better at returning reporters' phone calls.

"I have found it hard to find time to be press secretary," Brady conceded. He added that he can see the day coming when he'll be able to return all his phone calls.

A large number of reporters, from television, magazines and newspapers have complained to Brady -- when they could find him -- about his inaccessability. There also has been some criticism of Brady in the White House.

He's totally disorganized," one senior official of the press secretary.

The disorganization may result from the fact that Brady got a late start. Although he was the press spokesman for the Reagan Washington transition he was not named White House press secretary until Jan. 6

As a result he had to spend time forming a staff and planning how to run his office. There are still vacancies to be filled on his staff.

When he does give the briefing, and for all the criticism he has given two-thirds of the first 22, Brady can be very good. His sense of humor goes down well with most reporters, and he can be very disarming when refusing to answer a question.

"It's not full disclosure, folks," Brady said last week in trying -- not for the first time -- to explain why he would not give further details of a Cabinet meeting.

"The principle of the mind's ability to absorb what the seat can endure was tested to the limit today," Brady began his Friday description of the long series of budget-cutting sessions Reagan and Cabinet members had just concluded.

In Brady's absence, Speakes and Small have had varying degrees of success in giving briefings and handling reporters' inquiries.

Speakes, who was in the White House press office during the Ford administration, often has been sent in to brief with only a few minutes' notice and therefore little time to prepare himself.

He also was sent to speak in Brady's place to a luncheon group in the first days of the administration, where he delivered himself of a not very flattering, but quite apt comparison of reporters to ducks: "You have to feed them a morsel every so often or they bite you."

Small has been successful, in the eyes of the reporters.

Her first solo flight in the briefing room Wednesday did not go smoothly.

What is the president's position on Cabinet members discussing their private views in public? she was asked.

"Well, we'd have to ask him, wouldn't we?" she replied.

A minute later she said that the White House had strict rules governing contact between the White House and the Justice Department on pending legal cases.

"What are the rules?" a reporter asked.

"Do you want a legal seminar up here?" she asked.