The most notable way to handle all this information is using a personal Wiki.
A wiki (i /ˈwɪki/ wik-ee) is a website that allows the creation and editing of any number of interlinked web pages via a web browser using a simplified markup language or a WYSIWYG text editor.[1][2][3] Wikis are typically powered by wiki software and are often used collaboratively by multiple users. Examples include community websites, corporate intranets, knowledge management systems, and note services. The software can also be used for personal notetaking.
I never played with a wiki software but I can preview that in the back-end its need at least a database and a web server. Despite the fact that my free time is not so much I don't want to manage a distributed software architecture and a database to handle a simple conceptual notebook and to-do list.
Browsing around trying to find a solution to my problem i meet TiddlyWiki.
TiddlyWiki is a reusable non-linear personal web notebook. It's a unique wiki that people around the world love using to keep ideas and information organised.
With a more technical view
TiddlyWiki is a complete wiki in a single HTML file. It contains the entire text of the wiki, and all the JavaScript, CSS and HTML goodness to be able to display it, and let you edit it or search it - without needing a server. Although, having said that, there are some fine ServerSide adaptations out there.
With TiddlyWiki you can easily manage all your to-do list and all your stuff.
Also it's an heavy customizable self containable and extendible wiki.

Right now the last things I need to handle it's the synchronization between my computers. It's here where Dropbox with it's service start to help me. I think you don't need some other knowledge to preview how I share my TiddlyWiki.html between my machine or my smartphone with him and how I can easily maintain a synchronized Wiki with all my stuff organized .
As first point I hope I haven't made a lot of horrible English mistake and I hope this post can be of some interest for someone.
Have fun ;)