As the pirates of Silicon Valley bury their treasure, writers are drawing seven-figure advances on the subject -- call them the IPOs of publishing. Newsweek senior writer David Kaplan's The Silicon Boys and Their Valley of Dreams has already hit shelves, filled with gossip but few revelations. That leaves Liar's Poker author Michael Lewis and New Yorker staff writer John Heilemann in a two-man race. Norton editor Starling Lawrence based Lewis's $1.2 million advance on the success of Liar's Poker (also published by Norton), which sold more than 1 million copies worldwide on a $100,000 advance. "We're working as fast as we can," he says, to meet an October 25 deadline. Heilemann's HarperCollins editor, Adrian Zackheim, insists his book -- pushed back from fall to "sometime in the winter" -- isn't late; it's just comprehensive. Zackheim calls it "the definitive history of the digital revolution," perhaps planning to release a leatherbound five-volume set. That's a lot of mindshare.