San Jose, Calif. ? They will march into the predawn darkness, their battle plans carefully researched, meticulously MapQuested and fecklessly flecked with cranberry sauce. If shopping has a national holiday, it is Black Friday, the day after Thanksgiving, when the biggest bargains of the year appear on store shelves.

This assault on the shopping mall is the traditional second act in the American season of excess, which begins with Thanksgiving dinner and the unremitting drone of football. But frightened by a still-stumbling economy, retailers this year have stretched Black Friday to Black November — a monthlong carnival of consumerism that sounds vaguely like a terrorist organization.

“It really has gone from one day over Thanksgiving weekend to a four- or five-week festival of planning and research,” said Brad Wilson, creator of the website BlackFriday2010.com, one of many places shoppers can go online to find “leaked” Black Friday ads for chain stores such as Target, J.C. Penney and Sears.

Last year, Wilson launched BlackFriday2009.com on Nov. 5. “That was plenty early,” he said. “This year, we launched three weeks before that and immediately started getting 40,000 visits a day.”

Wilson’s site also offers shoppers an iPhone app, one of at least half a dozen such mobile maneuvering devices with which consumers can find the latest sale prices this year, maintaining maximum battlefield flexibility.

The leaked ads provide a treasure trove of price information, permitting the most aggressive Black Friday shoppers to plunder the plasma TVs first and end their day easing into a pair of half-off moon boots just as most people are waking up. Target is selling a 46-inch LCD TV for $449. Kohl’s is offering an El Paso Quesadilla maker for $12.99.

“It’s kind of exciting that you can get in five hours of shopping and then go to breakfast,” said Denise Alvord, as she and her 12-year-old son, Gunnar, waited Thursday morning for the Barnes & Noble to open at the Westgate Mall in San Jose. “I think it’s fun to be out there early, and fun to get good deals.”

According to a survey released by American Express this week, 100 percent of American women plan to do some holiday shopping this year, and many of them will be buying big-screen TVs for the terrified 88 percent of men who admit they will not go near the malls until they’ve emptied out again in January. Of the randomly sampled consumers in the survey, 31 percent said they would man the battlements on Black Friday. Or woman them.