login to sql

I'm tyring (unsucessfully) to write a page that demands a username and password, connects to an sql server (2005) remotely, and returns a page populated with information based on user access levels.

Specifically, user John Doe has supervisor rights so his user profile would let him see any item with a value of x or greater.

hmmm...simpification...

I want to be able to have multi level login to a remote server.

Does anyone know of a resource or tutorial that would help me to do this? I've tried mirroring examples I've seen but not too successfully.