THE FIRST writer I watched at work was my stepfather, E. B. White. Each Tuesday morning, he would close his study door and sit down to write the "Notes and Comment" page for The New Yorker. The task was familiar to him- he was required to file a few hundred words of editorial or personal commentary on some topic in or out of the news that week - but the sounds of his typewriter from his room came in hesitant bursts, with long silences in between...