I the JavaHelp User's Guide quite helpful when I was getting started with
JavaHelp; you can download it at:
http://java.sun.com/products/javahelp/download_binary.html#userguide. That
page also contains instructions for subscribing to the JavaHelp mailing
list, which is supported by one of the developers of the JavaHelp software.
That means you get get help from one of the guys who wrote the product; you
can't ask for much better than that.

There is also a JavaHelp forum at
http://forums.java.net/jive/category.jspa?categoryID=53. You may have to
sign up for Java Developer Connection before you can post to it; I can't
remember for sure. But I think you can look at the current posts without
signing up. A search of that forum may get you the answer to your question.

For what it's worth, here is a method that I use to set up help in one of my
programs; I _think_ it worked the last time I ran the program:

private void setupHelp() {

String METHOD_NAME = "setupHelp()";

/* Find the HelpSet file and create the HelpSet object. */
ClassLoader classLoader = this.getClass().getClassLoader();
HelpSet helpSet = null;
try {
 URL helpSetUrl = HelpSet.findHelpSet(classLoader, SDAC_HELPSET_NAME);
 helpSet = new HelpSet(null, helpSetUrl);
 }
catch (HelpSetException hs_excp) {
 Object[] msgArgs = {"\n", SDAC_HELPSET_NAME, moreInLog};
 String msg = utilities.logMessage(Level.SEVERE, CLASS_NAME, METHOD_NAME,
"msg009",
  msgArgs, hs_excp);
 JOptionPane.showMessageDialog(this, msg, CLASS_NAME,
JOptionPane.ERROR_MESSAGE);
 return;
 }

/* Create a HelpBroker object: */
helpBroker = helpSet.createHelpBroker();

/* Connect the Documentation item to the help broker. */
documentationItem.addActionListener(new
CSH.DisplayHelpFromSource(helpBroker));

/* Enable window-level help on RootPane. */
JRootPane rootpane = this.getRootPane();
helpBroker.enableHelpKey(rootpane, "events.editor", null);

/* Activate context-sensitive help button on toolbar. */
fieldHelpButton.addActionListener(new
CSH.DisplayHelpAfterTracking(helpBroker));

/* Set up field-level help for individual components. */
CSH.setHelpIDString(tableView, "eventeditor.table");
CSH.setHelpIDString(htmlSource, "eventeditor.htmlSource");
CSH.setHelpIDString(formattedHtml, "eventeditor.formattedHtml");
CSH.setHelpIDString(reformatButton, "eventeditor.reformatButton");
CSH.setHelpIDString(updateButton, "eventeditor.updateButton");
CSH.setHelpIDString(exitButton, "eventeditor.exitButton");
}

--
Rhino