The question: How do I print PDF documents with HTML DB?
The answer (maybe): PL/PDF
Looks like the folks at PL/PDF have some instructions on how to set it up in an HTML DB environment. For only $300, it seems like a good deal. It's not WYSIWYG, but the code for a complex master-detail report, which contains page breaks and headings on each page, is not that bad.
If you host your HTML DB site with Revion, PL/PDF is even included as a part of their package.
I have not tested this out yet, but am anxious to do so, as I'm sure it will come in handy!