When the time came to name Alison Rogers’ book about becoming a real estate agent, her publisher insisted on sticking the word flipping somewhere in the subtitle. So they did. Kaplan Publishing released her book, Diary of a Real Estate Rookie: My Year of Flipping, Selling and Rebuilding, and What I Learned (the Hard Way), in June.

“We squeezed the word in there because market research indicated that whatever the top 10 [real estate] books of the previous year were had flipping in their title,” says Rogers, a former New York Post editor whose real estate column for Inman News developed into the book. “The only people who don’t love my book are people who saw the word flipping, didn’t read the back cover, didn’t understand what the book was going to be, and then yelled at me on Amazon because the book didn’t make them a millionaire through flipping.”

Flipping: buying real estate, often cheaply through foreclosures, and then selling it quickly for hefty profit. It’s what Americans came to expect from real estate investment because of the housing boom—especially the “quickly” part.  If people themselves weren’t flipping properties, they knew somebody who was, or they had heard or read about it routinely.

One of the places they read about it was in books, as publishers jumped on the trend. More than 120 real-estate-investing titles were published in 2006, almost double the number for 2005 and more than three times the amount published in 2001, according to R.R. Bowker, a New Jersey firm that tracks book publication in the U.S.

In keeping with the go-go nature of the boom, the titles were myriad and sunny: Flipping Confidential: The Secrets of Renovating Property for Profit in Any Market; The No-Nonsense Real Estate Investor’s Kit: How You Can Double Your Income by Investing in Real Estate on a Part-Time Basis; Flip: How to Find, Fix and Sell Houses for Profit; Flipping Properties: Generate Instant Cash Profits in Real Estate. And on and on.…

But sales of real estate books this year are likely to fall short of what they were at the height of the boom. In 2005, consumers bought 223,000 books on buying and selling their own homes, according to Nielsen BookScan; in 2006, they bought about the same number. But by November 3 of this year, they had bought 172,000. So unless sales in the last few weeks of 2007 are particularly brisk, the final tally will be lower than last year’s.

The drop-off is even steeper for books about real estate investing. In 2005, 754,000 such books sold; in 2006, 662,000. By November 3 of this year, consumers had bought 458,000 real estate investment books.

Michael Norris, a senior analyst with Simba Information, a Stamford, Connecticut, market research firm, compiled the Bowker data for Condé Nast Portfolio. The number of new real estate investing titles will “certainly drop this year and next, for obvious reasons, as the market sorts itself out,” he says.

In the past two years, Crown Publishing, a Random House imprint, has published titles such as The Wall Street Journal Complete Real-Estate Investing Guidebook, Seven Steps to Sold, and 100 Questions Every First-Time Home Buyer Should Ask. But when asked about its current plans for the real estate books market, a spokesperson for the company said, “We have no projects planned at this time.”

New real estate books that are hitting the market show a shift in tone and topics. Richard Narramore, the main real estate book editor at John Wiley & Sons, says the publishing industry keeps a close watch on the real estate market, which is why the current trend is away from flipping and more toward sober subjects. “There are far more books on foreclosures than there were a year ago,” Narramore says. “We’re trying to guess like everyone else what the next hot trend will be in real estate. If the real estate market is going in a certain direction, we’ll go in that direction.”

Kaplan Publishing released a new title this August: Protect Yourself From Real Estate Fraud and Mortgage Fraud. The publisher raved to CNP that it’s “perfect for this time in the real estate industry.”

“We do respond in certain ways,” says Yvette Romero, Kaplan Publishing’s P.R. director. “But if you have a backlist, you’re not going to not have the books around, because the market is going to turn around.”