How to add files to project on google code?

I normally organize my project in multiple files. Now, for the first time I have created a project at code.google.com/hosting.

How to add files to the project?

The project has got directory structure and many files. I want them to be visible under trunk (like it is in other projects).

NOTE: I am novice in this area (I have no clue about what to do). I am searching for an UPLOAD button.

From stackoverflow

• You need to have a source code management system to be able to do that. Google Code typically uses subversion. Either download the commandline version or a GUI wrapper like TortoiseSVN. Then, you can upload all your project files.

  • Getting Started
  • Project Hosting FAQ
  • Google Code blog
  TheMachineCharmer : Thank you very much. TORTOISE ROCKS!!!

• Google Code uses Subversion for source control:

  http://code.google.com/p/support/wiki/GettingStarted#Working_with_your_Source_Repository_on_the_Source_Tab