I am really new to the whole concept of content management systems (to the point where I'm still not sure how it is structured - is it a set of codes that you insert into your own html document, or is it a complete package that you can customize visually?). What I would really like to know is whether there are any sample websites done with the different CMS's such as Wordpress, Drupal or Joomla that I could take a look at so that I can see what they can do, and what they look like from the outside and inside if I view the source code. When searching for information, I find it is easy to find answers to specific questions, but next to impossible to find something that explains the big picture. I need to know about the forest before I can understand the trees, if you get the analogy.

Also, is there any book or tutorial that will lead me by the hand in building and customizing a dummy website using Wordpress from the ground up? I have downloaded Wordpress, but have no idea where to go from there.

Thanks for any suggestions and help.