With modern large hard drives it is very easy to not keep things neat and organized, sort of like when you first move into a larger house.
Make folders to organize all sorts of things, in email and on your desktop. Move them around as you finish a project, putting them back into Documents or any other place that makes sense to you. Even use folders for organizing things on the fly, like when you are wanting to clean up your Desktop but are not sure if you want to through things away, put them in a folder called “throw away in three months” or whatever you want to call it.
Smart search folders
Almost as good as sliced bread, smart searches are like folders whose contents are defined by an always-on search of your computer. This means that you do not have to worry about exactly where those files are; your smart search folder finds them. More importantly, you keep just one copy of a particular file but it can “show” up in multiple smart search folders.
Bookmarks or favorites
Keep track of websites you want to return to by bookmarking them, rather than search for them each time you want to find them (or using your history of recent sites in the address bar.) You can even organize your bookmarks into folders, and most web browsers have a place just below the address bar where you can put those sites you want to get to often.
I may harp on this but backups are essential, keeping copies near you and in the “cloud” of the Internet. The basic idea is to first put a price on your data, pictures, music, and videos. And, then use a percentage of that cost up front to backup data to an external hard drive, to the cloud, to DVDs, or flash drives. All the organization in the world won’t help if your data disappears.