When Amazon banned Santomauro from its marketplace a few weeks later — due to e-mails he had sent to Taylor — Santomauro distributed Taylor's home address and e-mail account to his thousands of subscribers. The AJCongress official was immediately hit with a barrage of threatening e-mails — one of which led Taylor to contact the Los Angeles police.

"Since you support Zionists," the anonymous e-mailer wrote, "I'm sure you won't mind having your family members shot and your house bulldozed."

The Internet has been a boon for Holocaust revisionists, who have found few other mainstream outlets for their ideas and products. Earlier this year, Santomauro began selling "The Riddle of the Jew's Success" on the Amazon marketplace, which serves as a middle man between Internet buyers and sellers. The book, which was written by Theodor Fritsch, was first published in 1887 and became one of Hitler's favorites. In an e-mail to supporters, Santomauro wrote that the book explained how "Judaism is a conspiracy against non-Jews. Its aim is to fulfill the covenant and gain dominion over mankind by controlling wealth."

Santomauro reprinted 1,000 copies of a translation of Fritsch's book, and by September he had sold more than 100 of them. Taylor came across the book as part of her work with the AJCongress, where she said she is "in charge of monitoring antisemitism and anti-Americanism on high school and college campuses."

Taylor has posted a number of online reviews of books relating to Israel and Judaism on Amazon.com. In a review of a book edited by prominent left-wing Israeli historian Tom Segev on Israeli political dissent, she wrote, "If you like lies, revisionist history, falsehood, and numbers without statistics to back them up, then this is the book for you."

On the same day that Taylor bought "The Riddle of the Jew's Success" from Santomauro, she posted a review of the book. In it, she wrote, "Shame on Amazon and shame on you if you purchase this trash." Santomauro wrote to Taylor using the e-mail address he had received through the order, and asked her why she had written a bad review before reading the book. (Taylor said that she had read excerpts before purchasing it.)

Amazon prohibits sellers from having any contact with customers that is unrelated to the transaction. Taylor said that soon after, she received two more e-mails from Santomauro's personal e-mail account. One of which, she said, "talked about Jews masturbating over body parts." When Amazon asked for a customer review of her experience, she sent along the e-mails from Santomauro.

In an interview with the Forward, Santomauro said he sent the e-mails only after Taylor asked to join his ReportersNotebook e-mail list. Taylor countered that she did request to join his list — for monitoring purposes — but only two days after receiving the first batch of e-mails. Neither claim could be confirmed, because both Santomauro and Taylor told the Forward that they had deleted their e-mails from the relevant time period.

This is not the first time that Santomauro's various email lists have gotten crossed. He also runs a roommate-matching service on the Internet. In 2003, he was swamped with complaints after his Holocaust revisionist e-mails accidentally were sent out to his real estate clients.

In this case, Amazon wrote to him October 11 telling him he was "no longer able to sell on our site," because of "inappropriate e-mail contact that originated from your e-mail address."

Santomauro told a different story in e-mails that he sent out to his supporters after he was banned by Amazon. He immediately wrote to his ReportersNotebook list, proclaiming that he was the target of a "professional campaign to smear booksellers that deal with the 'Jewish Question.'" He told his readers to protest to Amazon. Then he sent out a separate e-mail with Taylor's home and e-mail addresses. Santomauro told the Forward that he sent out Taylor's personal information in order to help journalists who wanted to write about the story.

Since then, Taylor said, she has received about 50 threatening e-mails. A friend helped Taylor track down the person who sent the most threatening e-mail, and she reported it to the domestic terrorism unit of the FBI.

Santomauro said he saw nothing wrong with his decision to publicize her address: "For somebody who is trying to destroy my livelihood, and saying things in derogatory ways — I didn't see what was wrong to announce her address." About the threatening -emails, Santomauro said, "How do I know it's not a campaign being fabricated in cahoots with the [Anti-Defamation League]?"

Neo-Nazi Internet magazine National Vanguard picked up on Santomauro's story and reprinted his telling of it. It did not include a response from Taylor. The magazine identified her as an "alleged operative of the ADL" because of an e-mail she wrote to one of Santomauro's supporters, saying she intended to pass along the book to the organization.

An ADL official told the Forward that the organization has had no contact with Taylor about the incident.

Taylor said that the threats have diminished, However, the AJCongress official added that she is ready to pursue a restraining order against Santomauro if she receives one more. She also has written to Amazon, asking the site's operators to display prominently the fact that sellers on the site will receive buyers' contact information.

"Had I known I was giving all my information to Santomauro," Taylor said, "I would have done things differently."