I always use h1 for the book title. Then descend as needed. If it is an omnibus, the individual book titles get to be h2 and their chapters are h3. If it is a standard novel with chapters or a short story collection, those are often assigned as h3 also. I have never gone deeper than h4, and that is seldom, because I only do simple fiction, and that very rarely has sub-chapters.
You can use the h
x with a title: tag if you want the name to appear differently in the TOC than it appears on the page, or even set the h
x to display:none and then create your
displayed heading text(s) with <p>s or <div>s.