On my hard drive I have a folder named Photoshop Extras which is divided up into sub folders of Brushes, PlugIns, LayerStyles etc. Inside Brushes I have one folder for unzipped and used brushes also subdivided into brush subject. The same for PlugIns etc.
That way the only files that are in Photoshop are all default.The default must remain in the actual Photoshop folder to stop it throwing a fritz when starting up.
Sometimes to make it easier if I have downloaded several files I will create a temp folder titled Brushes Install so I know I havent unzipped or looked through them yet.
To make it easy to give all designers proper credit all files have the designer's initials in the file name and alongside the Brushes and PlugIns folders I have another folder titled Terms Of Use which has a single copy of all relevant info to save space.
Now...has that confused you enough?