Authors are shrugging off publishers to self-publish their work. Publishers are advancing into retail. Barnes & Noble is getting deeper into the gadget business, and Amazon is stepping into publishing.

There is a Wild West quality to the book business these days, and it is on full display at BookExpo America, an annual trade show that draws tens of thousands of authors, publishers and booksellers.

For three days the attendees wander the exhibit halls, mingling, promoting books, listening to speakers and collectively musing over the state of the industry over the past year. They have a lot to discuss. E-books have exploded, surpassing print sales for some new releases. The struggles for many brick-and-mortar bookstores have deepened as their customers began downloading books onto their e-readers from home rather than heading to stores.

Easily eliciting the most chatter was Amazon?s announcement on Sunday that it had hired one of the industry?s best-known veterans, the publisher turned agent Laurence J Kirshbaum, to head a new imprint for Amazon that will publish general-interest titles. On Wednesday Amazon said it had acquired a book by the thriller writer Barry Eisler, who had announced this year, with much fanfare, that he was abandoning a six-figure contract with his publisher out of dissatisfaction with the traditional book industry.

Some anxiety over digital publishing was tempered by the fact that while e-book sales are huge in fiction, especially genre fiction like romance, mysteries and thrillers, they have barely registered in children?s books, reference books and a lot of nonfiction categories. And, publishers said, the spread of e-books could make the whole publishing pie bigger.