Not exactly sure what you are asking here Milt? The way I run it is:
Main account: You.
This account is the master and should have the PSN wallet (In other words you control what content is bought on the PSN market place. One of the features I really like about the PS3 is that even though you bought the content, any sub account on your PS3 can use the content as well ... unlike XBOX
Sub accounts: Kids, friends, etc.
These accounts have the ability to play online, etc. but unless they set up their own PSN wallet, they can't purchase anything off the PSN market place.
1) Each account, master or sub, must have their own unique e-mail address.
2) When I made my son's first sub account I listed his then age of 8. This created a problem with Burnout Paradise. EA will only allow players 18 years and over to play on their online servers, no matter the rating of the game being played. I had to make him a new account an give him an age of 18.
As far as I am aware you can make as many Master accounts as you like, so as long as you are not worried about losing any trophies or don't have money in an all ready created PSN wallet, I would just start from scratch.