Great, welcome to the fantastic world of Xerte!!
You'll soon find out that were not ones to tell people to go read - i would advise it if you are new but your always welcome to ask for help...
You need to choose which auth you are going for, for a small set of users db auth should suffice. if you edit auth_config.php and select that and then login to management.php with the admin details that you set at install time then go to the users tab you should be able to add users.
John