Security Assist - Allow for Admin to first approval users

Here is the logical we need:

General user and create an account be registering
(a hidden field would first initial set a filed called "access" to "notapproved")

Upon successful registration, user would be present to a "thank you"page that says "we must review your application etc We will let you know via email when your user log in activate)

An admin can log into a administrative front end page, upgrade the users access to something else that allows for access to site (i.e. access=approved) and then the admin can manually send out an email from their email client to notify the user that they can start using their log in.

All of the stuff above is fine, I know how to do that. My real question is:

What would be the best way to let the admin know that I new user has been created and needs to go thru the manually approval process?

Ideally when we would like upon a sucessful registration as outlined above an email from be sent to the admin that says something that " a user called 'delta' has been created" That would let the admin know to log in and approve them.

Does this make sense?