Best Hierachy Setup?

Many pro studios make the client buy an external hard drive, which is dedicated to their project and stored in a safe, clean location after the project's done.
 
Beyond that, it all depends on your personal preferences. For me, it's a single top-level folder that contains one subdirectory for each song, with the directory structure duplicated on an external backup drive. I give the same name to both the song folder and the cwp file, making it easy to back up changed files via a generic batch file.

It's simple although I have changed how I do it. First making a new project you put in its own folder. Every project has a folder. For a name I have the Name of the Song condensed if necessary, and what speed it was recorded at. Don't say I record all of mine at 44.1kHz or 48kHz, because someday you will not and you will not remember. At least in Sonar if it still has it (I have Sonar 7 which may be upgraded but what I do is not that much anyway to need something better- it handled 54 audio tracks (out of total 64) on my old XP computer, but not virtual synths whatever those are called). But in my Sonar I have menu item "File" -> and every version I have had has submenu item under "File" called "Info". That is where I put anything else, unless I want to make a notepad text file of the project.
Guess that is about it, except perhaps storing the Project Folders on another harddisk or partition to have a copy of everything. Except for WOV files (picture files of graphics for waveforms which are all in one folder - not much you can do about that) but also store that as a copy on another harddisk or partition of the same disk drive.
 

AT
It all depends upon the kind of studio.  A home project studio for your own stuff and a few select other people's projects is fairly simple.
 
Disk>Projects>bandname>CDname>song
 
That should take care of 90% of work.  I also keep the "master mix" w/ the song project and in the CD folder keep a sub folder called mixes for CD and mp3 copies.  Just burned a cd version of a song for a drummer that "didn't have anyway to listen to a download."  Drummers.  He is going to pick it up so he can add some brushwork to a blues song.

 
This is just about how I do it.  I must confess that I am anal.
For project files:
disc/sonar projects/artist name/cd name/song folder/archive folder
- the song folder is the same name as the song
- the song has a date and number (01, 02, etc) for date stamp and takes
- the archive folder is for old takes
 
For mix files:
disc/mix files/artist name/cd name/"alpha", "beta", "final" folders
- disc is different from project disc
- each alpha, beta and final folder has three sub folders
  - original exported-from-Sonar wave files
  - mastered WAV files
  - mastered MP3 files
- alpha folder is for pre-mix client review
- beta folder is for final client review
- final folder is for the cd-quality files
 
I back both discs up totally at the end of every session into a dated folder for each disc.
 
whew, I didn't realize I was this anal.
t