HTML Help Books
Even though HTML Help has been around quite a while it is still a relatively new technology used by few help authors. As such there arent many books specifically focused at HTML Help yet. This is going to change however. The kind people at HelpThink Press are working very hard on a series of books, four to be exact, which target virtually every aspect of authoring and programming HTML Help. The books are scheduled for release throughout the year 2000.
Until then youll have to do with "Official Microsoft HTML Help Authoring Kit" by Steve Wexler. This is a great book and I learned HTML Help from it, but unfortunately, as with virtually all books from Microsoft Press, all code examples are targeted at either C++ and/or Visual Basic programmers.
Designing
HTML-Based Help with RoboHELP HTML 2000
Offical Microsoft HTML
Help Authoring Kit
The Developer's Guide to HTML
Help
The HTML Help Handbook
The HTML-Based Help Idea Book