Retrieve all users from sql Database

Hi

My application generates various types of bills but each user should only be able to retrieve their bill. I therefore need to link users to accounts. I planned to do this by just linking the users table to my accounts table, is there a better way?

My main problem is retrieving a list of all users to assign accounts to them. Can anyone direct me to more information or tell me how to retrieve a list of all the users from my sql database (default provider) to VWD 2008? How do I even view the users in sql server management studio express?

 Thanks in Advance...
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