hi lilyrain, I have always had great experience at project seven http://www.projectseven.com
When I initially tried to learn css I discovered they have great free tutorials, and great support.
I actually have learned quite a bit with project seven. If you have problems, they have a great newsgroup http://www.projectseven.com/support/
Also, you can post on dreamweaver's newsgroup too. (you can post css questions there, even if you don't have dreamweaver.)
Also, another great resource is w3schools http://www.w3schools.com/css/default.asp there you can go ahead and bookmark, as that site will be quite beneficial to you.
Also, look at http://www.echoecho.com/css.htm for basic css info.
If you have any questions, and are not getting answers, post here.
Wish you the best.