If I were you, I would get myself a good book on the subject.
I personally like HTML, XHTML, and CSS, Sixth Edition. I bought it at a local Barnes and Noble and I've found it quite handy for questions like this. Also, look around for some good CSS books (sans HTML).
Eric Meyer would be your best bet in terms of authorship.
PS:
CSS 3 Adds lots of cool features like rounded corners and drop shadows.
Many of these new features are not yet supported by IE, FF, Opera, chrome and Safari.
(Chrome, Opera and Safari need new abbreviations, really.)
Try looking at the CSS article on Wikipedia.
http://en.wikipedia.org/wiki/Css1#CSS%5F1