Free on the April PC Advisor cover disk.
You should be able to import the existing site, modify it in NOF, and republish it. It doesn't require much knowledge of HTML. It is much like a page layout program. Place a text frame, graphic, or table on the page. Drag a navigation bar onto the master border. Drag margin guides to adjust the size of the page or drag elements to resize and reposition them.
If you post a link to your site, I will check to see if it can be imported with at least some degree of success.
My website click here was built with NetObjects Fusion MX, free on an earlier PC Advisor disk. I taught myself since I started with NOF version 2.02 about two years ago.