I realize this question was originally asked a while back, but others may come looking for the same info.
I've been trying to become more efficient with CSS and blending it with html and this is now my favorite way of learning. First I get all my education from
http://www.w3schools.com/css/default.asp (their site also has html lessons) and then I get a true understanding by hands on trial and error. => Install the Firebug plugin for Firefox, then go to your current URL - or anyone's site for that matter - and open up Firebug. You can then make changes to your heart's content (or brain's content in this case) and you will see the immediate results of those changes.
I used to visit someone's site and say "how do they do that?". Sure I could have used view source, but now I just open firebug and start 'changing' their code and manipulating their site. Of course, it only changes in your browser and will go back to normal when the page is refreshed.
Christy