Admin/Customers Login

Hi,

I am developing a shop and I already created an admin login using
act_as_authenticated.
I now want to create the following:

  1. Admin can create a new customer and assign her a discount level
  2. Admin can basically administer add/delete/edit/list customers
  3. Customer need to login in order to place an order
  4. Optional: When customers log in, they could see a history of
    previous orders they placed

I have been thinking about this for a few days and my logic says I
need to create a new ‘Customer’ object (and table in my db).
What I am having trouble with is how to implement the customers’ login/
administrating?

I’ve been trying to find a tutorial or howto anywhere, but they only
show how to place an order without logging in.

Any help will be much appreciated.

Elle