Over the last year i've been using an Open Source Church Database called ChurchDB or ChurchInfo.   This database allows non-profits(specifically targeted at churches now) to track members, create directories, track donations & pledges, and other perform membership functions.  Unfort this application doesn't have some basic functions. 

I've released a version (in downloads) of this that allows for table prefix's and the ability to un-publish certain fields from the directory (Phone Numbers & Emails).   I'm currently working on an installation front-end that would enable the table prefixes (right now you have to edit the SQL file to put your own prefix in) and the modifications to the front-end to control unpublishing certain fields.