Nvu
There are a lot of web authoring packages about, both professional, Shareware and even Freeware Nvu is based on Gecko, the engine at the core of Mozilla. It claims to be super-fast, very reliable and conforming to all web standards. It’s an Open Source project, which means you have a wide community of programmers working on the project. And of course, you can download it and use it for free, nice.
Nvu is a WYSIWYG editor, enabling you to layout your pages directly instead on dealing with straight code and flipping between code and browser views. It has been designed to be very easy to use, making professional-looking pages possible with the minimal of HTML knowledge. Support includes XML, CSS and Javascript, Tools include a site manager, colour picker, Stylesheets and a CSS editor. It comes highly recommended. There are Mac, Linux and Windows versions, so be sure to download the correct version for your system.