TERROR IN OKLAHOMA CITY : Explosive Recipes Fill Books, Cyberspace : Information: In a democracy, there’s no secret to making a murderous bomb. Just browse in a bookstore, or surf the Internet.

Only hours after the bomb that shook America, someone posted directions for a repeat performance on the Internet.

It was all there--even a diagram: Mix two widely available chemicals, slap on a “booster,” attach a detonator and almost anyone can have a bomb like the one being called the deadliest in U.S. history.

“There you go!” boasted the Internet citizen. “Thought that might help some of you.”

Perhaps it’s the price we pay for freedom of speech: Directions for devastation are widely available at bookstores and on the Internet--where text on terrorism is interactive (ask questions on bomb building and get answers with the click of a mouse). While it’s not clear if the suspects in the Oklahoma City case drew from manuals or on-line expertise, some experts say this increasingly abundant information will only serve to arm more fringe groups in the future.

“Democratization and dissemination of the techniques of terrorism,” says USC terrorism expert Richard Hrair Dekmejian, “is going to breed more violence.”

Lack of technical expertise is no longer an impediment to terrorism. As The Guardian of London put it, “The West . . . faces a new threat from ‘amateur terrorists.’ ” Warns Dekmejian: “Imagine what someone with a little sophistication can do.”

Books on bomb-making can be had almost anywhere, from Bookstar to Barnes & Noble to Borders (which doesn’t carry the books in-store, but will order one at the customer’s request). Terrorism expert and author Neil C. Livingstone says he has documented more than 1,600 “mayhem manuals”--books with titles like “The Anarchist Cookbook,” “The New Improved Poor Man’s James Bond,” “How to Kill” and “Exotic and Covert Weapons.”

They also can be had on the Internet and through mail-order companies such as Loompanics Unlimited and Palladin Press. Livingstone says he bought one at National Airport in Washington. “Only in America,” he says.

On the Internet, there are several “discussion groups” where information can be traded anonymously via e-mail. There’s also an on-line explosives “site”--a virtual manual--known as The Big Book of Mischief.

On one discussion group recently, tips were traded on the best way to build the kind of bomb used in Oklahoma City, on how to synthesize an explosive known as Thermit and on how to build a pipe bomb. There also was talk of how to make sarin, the chemical that killed 11 people in last month’s Tokyo subway gas attack.

One Internet query read: “I am a child of 13 and am very interested in explosives.” Meanwhile, the introduction to the discussion group listed its do’s and don’ts of bomb-making: “If a device you build fails to work, leave it alone for half an hour, then bury it.”

There is anecdotal evidence that this kind of information has been put in motion. One of the 1993 World Trade Center bombers was arrested with manuals in hand. In 1989, four Bethesda, Md., teen-age boys were killed when a homemade pipe bomb accidentally went off. They were following instructions from a bomb-making manual. And in 1987, an Escondido teen-ager blew himself up with homemade bombs. The “Improvised Munitions Black Book” was found nearby.

“It’s going to be a guy with a PC that will be our Carlos the Jackal of the future,” Livingstone warns.

He calls mayhem manuals (and similar information on the Internet) “obscenely violent” and says that they should be restricted to those 18 and older, outlawed for export and interstate trade and limited to experts in some cases. “Even pornography is regulated in some form,” he says. “But we will sell a child a manual on how to do a terrorist attack.”

“That kind of information should be removed from libraries, bookstores and the Internet,” Dekmejian says. “People need not know how to make bombs.”

The First Amendment has proved to be an impenetrable hurdle for foes of this type of information. In 1993, a West Hartford, Conn., college student was arrested and charged with inciting injury to a minor because his computer bulletin board--popular with teen-agers--featured directions on how to make a bomb. After civil libertarians cried foul and cited the First Amendment, the charges were dropped. (He was held on other charges.)

The federal government does restrict the flow of information concerning nuclear technology--although a magazine called the Progressive, in a well-known test of the Constitution, unleashed the secrets of the H-bomb in 1979.

Some experts would rather regulate the materials used in bomb-making than censor the blueprints. Veteran New Mexico explosives expert Edward M. Roy supports controlling ammonium nitrate--a main ingredient in the Oklahoma City bomb that is potent, cheap and easy to get--by adding chemical tracers (which could identify what store it came from) and by cutting down on the purity of the chemical (which would require more material for less punch). But, he admits, “that would be a major undertaking.”

Still others say instructions and materials are irrelevant. “I think it’s organization, doctrine and political context which shape the inclination toward terrorism rather than the availability of information or materials,” says UCLA political scientist David C. Rapoport. This talk of manuals and e-mail, he says, “exaggerates the significance of the threats and takes us off the real issue--the political conditions which cause this kind of violence.”

Cyberpunk author R.U. Sirius defends the right of people to publish and post the details of destruction, no matter how repulsive. “Information,” he says--citing the computer “hacker ethic”--”wants to be free.”

But even Sirius--a well-known “netizen” who used to edit Mondo 2000 magazine--is squirmy. During his work on a forthcoming Ballantine cyberpunk novel, “we were thinking of publishing information on how to build a small nuclear bomb,” he says. “But after I saw what happened in Oklahoma City, I thought, ‘My God, what if someone actually used this information.’ ”

Steve O’Keefe, former editorial director for Loompanics Unlimited, says, “I’m not a fan of these types of books, but I think everyone has a right to sell them and buy them.”