If you want to digitalize your notes and data, you might like the software "One Note" which comes with the MS Office 2007 and 2010 versions.
It makes sections for every topic and sub-topics.

When you find something on internet forexample an article related to lets consider for World War I and you copy that and send it to "One Note", it automatically asks you where to save it.

You tell it to put it in the section of Current Affairs World War I section. It will copy not only the article, but pictures, diagrams with it and also automatically save the web link addresses so you can track the web contents of the same website in future.

So this way, you can even save a lot of material related to every topic you want and then give it a thorough reading.