The scramble for survival in the New York publishing world provoked by the rise of the ebook has become so ruthless it makes the Wild West look like a Swiss finishing school.

Authors and publishers are squabbling over rights, internet retailers are slugging it out with bookshops, and tech companies are climbing over each other to produce an ebook reader that can challenge Amazon's hit, the Kindle.

The latest blast of gunfire has come from one of America's leading authors in the highly lucrative market of business self-help books.

Stephen Covey has announced he is selling exclusive digital rights to two of his bestsellers – The 7 Habits of Highly Effective People, and Principle-Centered Leadership – to Amazon, bypassing the traditional publisher, Simon & Schuster, that has up to now handled all his output.

The move has put a chill over New York publishing houses already struggling to keep up with the ebook revolution. One of their big fears is that of becoming separated from their backlists, the titles that act as the cash cows of the industry, bringing in a steady and increasingly crucial income in the insecure digital world.

As jitters spread, some big publishers have moved to defend what they claim is theirs – the digital rights to the backlist.

Random House startled many in the book world this week by sending a letter to agents informing them that, in its view, the publishing house holds the exclusive rights to digital editions of the "vast majority" of its backlist titles. That made authors and their agents see red. They pointed to a ruling by the New York courts as far back as 2002 in which Random House itself failed in an attempt to block on ebook firm from publishing works by the late William Styron, author of Sophie's Choice, and Kurt Vonnegut. The ruling, upheld on appeal, found that copyright for books that were written before digital publishing existed, remained with the author.

Arthur Klebanoff, head of RosettaBooks, the ebook company that beat off Random House in 2002, secured Covey's exclusive deal this week with Amazon. He said: "We are very clear about this, the author controls the rights unless it is specified otherwise, and that was settled by the courts years ago."

Simon & Schuster, which took a knock over the Covey deal, was taking a softer stance than Random House but not accepting defeat. Adam Rotherberg, a spokesman, would not comment on Covey specifically, but said in general terms it was the company's "intention to publish the electronic editions to our backlist titles".

Simon & Schuster, like other big houses, is trying to protect income from print books by delaying the publication of new ebooks by four or six months after release of the hardback editions.

The spat in the US stands in contrast to Britain, where publishers broadly accept that they do not have the rights to the ebook editions of older titles, and authors accept that they should avoid offering ebooks to other publishers.

"There is a kind of gentleman's agreement," said Anthony Goff, an agent with David Higham, who heads the trade association for literary agents in the UK.

One reason for panic in the US is that there the ebook market has already grown to a significant size. Almost $16m (nearly £9m) of ebooks were sold in September, a year-on-year growth of 171%.

Amazon enjoys the lion's share of that market through its website and popular Kindle, and the deal with Covey is an indication that it intends to tighten its grip. This year about three million e-readers have been sold in the US, a number that could double in 2010.

Although the Kindle is the industry leader it is facing strong competition from the Sony Reader and the Nook, a new offering from book chain Barnes & Noble.

A further shake-up lies ahead when Apple wades in, as expected in the spring, with the Apple Tablet.

As these behemoths fight it out in an increasingly ungainly display of muscle, the big question is what happens to authors and their readers, which is after all what the fuss is about.

Bestselling names such as Covey are likely to prosper, as will their fans who will benefit from knockdown prices. Amazon is selling some titles for as little as $7.99, massively below their paper price.

Less well-known authors have yet to reap any rewards.

Paul Aiken, head of the Authors Guild, pointed out that most ebook deals award authors 25% of royalties, which, given the lower costs of publishing digitally, is only about a half of the accepted rate in print books.

"Up to now that hasn't been much of an issue, because the ebook market was so tiny," Aiken said. "Now that's changing, and authors with clout are starting to demand more."

• This article was amended on Thursday 17 December 2009. We said Simon & Schuster "in tandem with other big houses" is trying to protect income from print books by delaying the publication of new ebooks after release of the hardback editions. To clarify, we meant to say the company is pursuing a similar strategy to others, not that it is co-ordinating its strategy with them. This has been corrected.