for crucial things i prefer buy it because talking about satisfied never lie so think to buy it .Don't you want something good for your project
so go and buy it .it's better than you find it for free, i know you can buy it.
LOL

If you really want a WYSIWYG editor, then I'd have to say go for Macromedia Dreamweaver. But do keep in the mind that the costs for that program are not exactly ideal; they border on the costs of Photoshop.

On the other hand, I'd really recommend that you not use a WYSIWYG editor. More often than not (Dreamweaver is not an exception), WYSIWYG editors put the CSS styles within the html code itself (you know like <a href="#" style="color:#000;">Click</a>), which destroys the purpose of having CSS in the first place. Moreover, it makes your code messy and more bulky. If you put the same style for all link elements, then you've just copied the same code a good dozen times and wasted a bunch of space that could easily be saved with an external CSS file.

Now onto a good non WYSIWYG editor. Truely there are TONS of these. I myself use Notepad++. It has tabs, making it nice to navigate. It also has built-in highlighting for a number of languages besides CSS (say in case you wanted to code in php or something). For me, it so far has covered most of my needs.

-Cssed ------ this one is purely for editing CSS, hence the name
-gedit ------ I used this at school before...it was okay, I suppose. But I do remember not liking it all that much.
-GLeDitor ------ Written in pascal...
-jEdit — written in Java. From what I've used of it at school, I've liked this editor a lot. It has numerous useful functions (such as the split screen).
-Leafpad
-NEdit ------ Used this one at school too. It was nice--loaded quickly. Clean and to the point.
-Notepad2 ------ I was considering this in addition to Notepad++