The reason many people struggle to find a way of structuring their photography is because there are so many avenues you can go down in regards to file structure. Another key reason is because many of us will take the photos BEFORE having the folder structure in place. While this isn't a major issue for the 'average' person taking a handful of photos a week, as they will just throw these photos into a generic folder (quite often the year they were taken in). The problem though, for photographers at least (whether amateur or not), is this can cause huge headaches later on - primarily during the 'sorting and editing' phase (I found out the hard way!).
I have only been 'properly' taking photos for 10 months now, but like most people, I also have a huge collection of family photographs spanning many years. I'll explain how I structure my folders (both my 'professional' stuff and my personal photos), and tips on how to name your files for easier browsing later.
Before going and making loads of folders, I'd suggest looking through the photos you have currently and working out how you could structure these folders around the photos you already have. This factor alone will determine how you will structure it all, so spend time planning it out properly, it will save you hassle later down the line.
If you're into photography and quite often put photos out there on the Internet, then it may be worth differentiating between your personal photos [pictures of family, friends and the like], from those that you don't mind people seeing. Separating these can make the process of sorting out your file structure that bit easier, as well as becoming essential when we get to backups.
While I'm not going to give details about my personal photography, it follows a very similar structure as my "Professional" photography folder. My tips for coming up with a file structure are to take a look at what photos you have already and work out what (if any) categories they fit into, then also to decide if there are any areas that you wish to develop in.
As is mentioned in the notes under panoramas, HDR and Photosynths, these are a little more complex in terms of what images go where. As you take more photos, you will come up with a more logical way to structure your folders. My panoramas folder looks like this:
This is one of group where I've split the panoramas of the subject/event - Ferrari Racing Days- into logical folders.
Within each folder, there are several photos; those needed to create the panorama, and the final stitched image. As was described in the folder structure image above, there is a "Base Files" folder containing the 'raw' images, then the final image itself.
The folder structure adopted is similar for my HDR and Photosynth photos also.
Part of photography is managing your files; without it, years down the line, you'll get yourself in a pickle looking for some important photos. Take an hour out of your day to properly structure your photos and get your folders looking right.