I've just completely populated the "Book" category (see the Categories list in the right sidebar column) with all of the content we've ever published on books here at the TOP TypePad blog, going all the way back to Day One.
It took me all day to get it done. Seriously.
It was such a slog that I doubt very much I'm going to ever succeed in "categorizing" all of the site's past content, although I won't give up that idea just yet. Next up, I'm going to try to populate the "Random Excellence" category.
At the very least, though, I'll try to add a category to all the future posts so that eventually most posts will be searchable by category. In the meantime, check out "Books."