Harold Clurman, the venerable theater critic and director, found only two of his books on the shelves of the new Performing Arts Library at the Kennedy Center during the reception following the dedication of the facility last night.

A bystander asked a passing library staff member if it were all right if Clurman autographed one of his books. Certainly, said the library worker. Clurman obliged, but as he signed his name he asked where the rest of his books were.

"I'm sure they're on order," said the librarian.

Clurman particularly recommended that the library acquire his "The Divine Pastime."

"We'll look into it," replied the librarian.

"Don't look into it; just get it," grumbled Clurman.

There are only 3,000 books in the news library. But there also are a number of recordings, videotapes and magazines. And there is a computer terminal hooked up to the card catalogue of the Library of Congress, which is runing the library with the Kennedy Center.

The dedication was marked by a panel discussion in the Terrace Theater on the subject of "The American Musical." Participating were Clurman, choreographer Patricia Birch, author James Michener, producer and designer Oliver Smith and producer Roger Stevens, who also happens to be chairman of the Kennedy Center. Librarian of Congress Daniel Boorstin moderated.

Valiant attempts were made to define what musicals are all about. If "Zooy Suit," which Birch is working on, had a few more minutes of music in it, it would be a musical instead of a "play with music." This would mean 26 union musicians would have to be hired, "and we couldn't afford to bring it to New York," she said.

Michener expressed his awe for such shows as "Kiss Me, Kate" and "West Side Story." "They have an invention, a richness, an imagination entirely beyond my capacity. I never could have conceived them," he said.

Sometimes the creators of musicals place too much emphasis on the books, observed Smith."Books are to be read, plays are to be seen."

Birch tried to steer the discussion to a consideration of new musical forms, but Smith expressed his disdain for rock musicals.

Stevens griped at length about the burdens of producking. "You should always do a musical to make money," he offered, because "raisking money is the only charm (about the job) other than being the football for what you call the 'creative elements.'" He cautioned that "there is no such thing as an investor" in a musical; "it's rank speculation."

Sometimes, "It almost seems as if there is a conspiracy among the stagehands and the musicians to make up very complicated rules to keep you from being successful and make your possibility of return even more limited," said Stevens.

But: "When it works, it's marvelous," concluded Stevens. "There is no thrill greater than a cheering first-night audience."