In response, the Authors Guild, the largest organization representing published authors, asked members on Tuesday to remove links to Amazon from their Web sites, said Paul Aiken, the guild's executive director.
The guild's move comes a year after Amazon began allowing customers to sell used books on its site.
Aiken said the 90-year-old guild has acted now because Amazon has begun prompting customers, who recently have purchased books, to resell the titles on Amazon.
"We suggested to members that it was in their own self-interest not to undermine their book sales by sending Web site visitors to Amazon," Aiken said. "Amazon is turning new book buyers into a used-book marketplace. That hurts profits of publishers and the royalties for authors."
An Amazon representative said the online store disagrees that the sale of used books hurts authors.
"If a customer reads the new author and likes the new author, the customer will be inclined to buy their books in the future," said Patty Smith, an Amazon spokeswoman. "It's all about giving customers options."
Smith added that about 700,000 Web sites post links to Amazon.
Sales of used goods are one of Amazon's fastest-growing sectors. The sale of used books accounts for about 15 percent of overall book sales, the company has said. And profit margins are higher, often 85 percent, on used goods than on many new ones.
For every used book sold, Amazon charges 99 cents and takes 15 percent of the asking price, Smith said.
Aiken said that legally, there is little an author can do to stop the sale of used books.
"As far as we can tell it's legal," he said. "The rights holder can only control the first sale of a book. Resales are out of the control of copyright law."