Has always wanted to learn CSS + div, but don't know where to start, so please everybody some directions!

Start here: http://www.w3.org/

Go through that site and read about:
http://www.w3.org/standards/webdesign/htmlcss

Then resources from this forum:

Brouser compatibility:
http://www.webmaster-talk.com/html-forum/82136-browser-compatibility-checker.html

Web Standards:
http://www.webmaster-talk.com/html-forum/151306-the-web-standards-curriculum.html

Clearing floats:
http://www.webmaster-talk.com/css-fo...you-clear.html

Absolute positioning:
http://www.webmaster-talk.com/css-fo...-when-not.html

Centring your website:
http://www.webmaster-talk.com/css-fo...r-website.html

The help on this forum is normally good for people learning.
Questions regarding HTML go in the HTML forum:
http://www.webmaster-talk.com/html-forum/

Questions regarding CSS go in the CSS forum:
http://www.webmaster-talk.com/css-forum/

and, the main key is to practice

After you're done learning, you can try to post at
http://www.csszengarden.com/
[you have to create a great CSS, for an existing xHTML]

you can learn online from the top links, but I think the important thing is to do first and when you meet some question, you can find the answers online.