I am a complete, total beginner in programming, although I do have knowledge of CSS and HTML.
I would like to learn Python. I downloaded lots of source code but the amount of files and the complexity really confuses me. I don't know where to begin. Is there a particular order I should look for?
Thanks.
EDIT: Sorry guys, I forgot to mention that I already have both the online tutorial and a couple of books handy. I basically I don't quite understand how to "dismantle" and understand complex source code, in order to grasp programming techniques and concepts. 
EDIT2: Thanks for the extremely quick comments, guys. I really appreciate it. This website is awesome.
To understand source code in any language, you first need to learn the language. It's as simple as that!
Usually, reading source code (as a sole activity) will hurt your head without giving much benefit in terms of learning the underlying language. You need a structured tour through carefully chosen small source code examples, such as a book or tutorial will give you.
Check Amazon out for books and Google for tutorials, try a few. The links offered by some of the other answers would also be a great starting point.
How can a total, complete beginner read source code?