1) Can a pitch document actually sell a book to a person I have not met in person?
This is one of the ways that the world of comics and novels differ most significantly, I've discovered. Comics publishing is a world in which a pitch for a series can result in a deal, in the best case scenario. In the world of novel publishing, on the other hand, that's not the case.
(The caveat here is that I'm talking largely about writers at the beginning of their careers, those who haven't yet sold a novel, but it is largely true of writers in my position as well, who haven't yet established a solidly-marketable "brand" name. More about this in a moment.)
In the world of novel publishing, pitching an editor is an attempt not to sell them a novel, but to get them to read a novel you've already written. A successful pitch ends with something like "Sounds interesting, send me the manuscript and I'll take a look."
Now, it's possible that a pitch and a sample chapter can result in a book deal. There was example of such a deal just in the last month or two that was reported pretty widely in the genre blogosphere, where a first time novelist had sold a novel series on the strength of a proposal and a sample chapter. But such a thing is so vanishingly rare that when it happens it is reported widely in the genre blogosphere. For all intents and purposes, though, it's best to consider it impossible.
As to the matter of sample chapters, for a writer trying to sell their first novel, I'd strongly recommend against writing just the sample chapters and then shopping them around. The reason being, that an editor whose read those sample chapters will, if they like what they've seen, ask to see the rest of the manuscript. If the rest of the manuscript won't be available for another six months or year or longer, the possibility exists that the editor might not be interested in seeing the manuscript when it's ready. And even in the best case scenario, when the editor might be willing to wait that long, this is an instance where you want to strike when the iron is hot.
(Another caveat. The preceding is largely the case for writers who have already sold a novel or two elsewhere, but are trying to sell another novel to a new publisher. However, selling a second or subsequent novel to a publisher who has already done a novel with you is a different scenario. I've sold somewhere just north of a dozen books, I think, and while I've never sold a first novel to a new publisher with anything less than a full manuscript in hand, in every instance where I've sold a second, third, or fourth novel to a publisher it's always been on the strength of a pitch alone.)
The other question that Bill asked was about agents, but that actually opens up a whole other can of worms. So I think I may stop here for the moment, and start in on agents in a while.