Richard Nixon's voice will haunt the nation's airwaves, beginning today.

The White House tapes that forced his resignation as president and sent his top aides to prison were last played in public in 1974 for a very select audience crammed into the courtroom of U.S. District Judge John Sirica for the Watergate coverup trial. Years later, they were made available to researchers willing to trudge out to the National Archives in College Park simply to listen to them--no copying allowed.

This morning, after years of litigation, they will be handed out to the first group of buyers, finally made public without restrictions at a pricey $18 for each 30-minute cassette.

The words may be familiar to those who remember the Watergate scandal, but the intonations, the pauses, the throat-clearing in the midst of talk in the Oval Office about proposed black bag operations and mugging teams will give new meaning to the dry transcripts that have been released before.

"In a sense, they bring history to life," said White House counsel John W. Dean III, whose March 21, 1973, warning to Nixon of "a cancer . . . close to the presidency . . . growing daily" will be one of the discussions available for purchase.

The collection consists of about 12 hours of tapes played at the 1974 Watergate coverup trial and another half hour that Watergate prosecutors used at the trial of a related scandal involving Nixon's hike of milk price supports in exchange for surreptitious campaign contributions.

"Better go get a glass of milk," then-White House aide John D. Ehrlichman says toward the end of the milk-price meeting. "Drink it while it's cheap."

With a full set costing $702, only 18 have been ordered so far, largely by broadcast networks and other outlets preparing to play choice excerpts on radio, TV and the Internet. The Cutting Corp., the Bethesda company that the Archives commissioned to make the copies, said 40 other purchasers have made individual selections.

"There's no real news in them, but I think these tapes will get a great deal of play on the air, said CBS News correspondent Eric Engberg, who covered the Watergate scandal. "There's been a great deal of silly commentary about how the Clinton-Monica Lewinsky scandal compares to this. All you have to do is listen about three minutes to see the difference."

Karl Weissenbach, director of the Nixon Presidential Materials Project at the Archives, said an additional 251 1/2 hours of Nixon White House tapes reflecting abuses of governmental power will be available for copying and purchase by Feb. 2, but a complete set of these will cost more than $9,000.

Anji Cornette, an executive at Cutting Corp., which set the prices, said they were standard for all work the company does for the Archives. By contrast, the Lyndon B. Johnson Presidential Library in Austin, which makes its own copies of LBJ's tapes, sells them at $6 for cassettes lasting about an hour.

Dean said he was surprised to learn of the small number of orders for the Nixon tapes. The Nixon estate is seeking $213 million from the government for its 1974 seizure of his records, including the tapes.

"This may influence the judge in that case," Dean said. "It shows what the real market is out there."