Profile. User, ProfileManager confusion

[dgk]

I've used the Website Administration Tool to create a few roles and
users using the default (SQLExpress?) providers. But when I try to to
access them using the ProfileManager:

lblCnt.Text =
ProfileManager.GetNumberOfProfiles(ProfileAuthenticationOption.All).ToString

I get zero. What I really need to do is add some custom fields to the
user profile, which I've done in web.config and populate that data
when I create a new user. The custom fields are available using
Profile.xxxx so that much is working Users cannot create their own
accounts, that will be done by administrators.

But I can't figure out how to access the existing users, much less
create new ones. Any pointers greatly appreciated.