You might at first expect that its best to write articles on the general topic of books. While there is some benefit to that my experience is that its best to diversify your topics.

The public's interest in the topic of the day varies widely. For example just before Thanksgiving Americans search the web for "turkey stuffing recipe". I expect Canadians do so as well but in early October.

In inlink from a book-related site will be the most relevant, but some other topic may produce more inlinks.