Adding a "subpage" that doesn't show up in the navigation menu

click the "page" icon in the inspector and deselect "display in navigation menu"
you can hyperlink to your own pages in the inspector also under the "links" icon

As an iWeb newbie, I had occasion to do exactly this today. Here's how to remove a page from the navigation menu:
1. Select the page in the sidebar
2. Open the Inspector and choose the Page Inspector (2nd icon from left)
3. Click on the Page Tab
4. Deselect the check box that reads "Include page in navigation menu"

That's all there is to it!

<Edited by Moderator>

Well, yes that is one way of doing it, but it depends what you want to achieve? If you really want a subpage that will not show in your nav bar at all, then I would suggest that you go to inspector and page and turn off the navigation bar altogether. That way, you can create your own navigation bar and include exactly what you want and what you don't want.

You can then create sub pages that don't even have to be included in the navigation bar and can be linked straight to the page. I have done that with one of my web sites and it is very effective.