Telephone Directory

I need to create a database driven telephone directory for approx 3000 users for an intranet site.
My intranet team currently maintain a directory requiring manual updates, but I now need this to be automated.
I am an experienced web designer / Dreamweaver user, but have no idea of using Databases, though I do have Ultradev which I am happy to learn / use.

As a starting point, I need to know the following;

Our Intranet site is a sub site and forms part of a national site. We do not have the ability to have access to the National server side or change settings. I therefore intend to run the database via a local server on the network which everyone has access to, though, can i do this and create a database through a "Shared Folder". What settings MUST I be able to change (i.e do I need accss to ODBC settings)

ARe there any telephone directory software programs that can be purchased off the shelf and adapted accordingly that I can run via a network - any links appreciated

Apologies for my Naivety...!!
Many Thanks

How did you get on with this query. I am looking at doing something similar. Any comments?