My brother Kevin is a writer as well. His day-job is as a technical writer at Creo, a recently-acquired subsidiary of Kodak. He’s also launched a recent white paper-writing business called (funnily enough) Barefoot White Papers. He’s got a nifty blog there all about white papers, which I enthusiastically recommend.
Now we also do white papers at Capulet, so he’s kind of competition, but there’s plenty of work to go around.