Last Tuesday, Buzz Bissinger hopped the Amtrak train to Philadelphia from New York, where he had done a bit of publicity for “After Friday Night Lights,” a 12,000-word e-book that had been performing nicely since its release. But when he opened his laptop to check his ranking on Amazon, he found the book was no longer for sale there.

“I was stunned,” he said in a phone interview on Friday. “I thought it was some kind of technical difficulty.” (I had noticed a lot of people on Twitter shared his confusion.)

Depending on how you define it, he was right. Mr. Bissinger, the best-selling author of multiple books, including “Friday Night Lights,” had written the e-book as a postscript for the popular book about high school football in Texas. “After Friday Night Lights” traces his relationship with Boobie Miles, a running back whose football career was derailed by an injury and who has been on a hard road ever since.

Mr. Bissinger wrote the e-book for Byliner.com, one of a number of fledgling companies trying to make a go of it by publishing long-form works — not as long as a traditional book, but longer than most magazine articles — for digital readers. Mr. Bissinger thought the e-book, priced at $2.99, would be a great way to pay tribute to the relationship while also helping Mr. Miles, by giving him a third of the proceeds.