I suspect this won't be of use to anyone who isn't us, but on the off-chance:
http://www.wildlyinept.org/ci/index.php/membership (demo)
http://www.wildlyinept.org/ci.tar.gz (code)
It's a cheap and easy web app to track who's attuned to what. It uses SMF (Simple Machines Forum) for authentication; if you were a PHP ween, you could hack your own authentication mechanism in, but it'd be a bit of effort. As written, your SMF admins can edit anyone's entry; normal users can only edit their own entry. You can sort on any column by clicking the column name, it has a field for your spec, etc. Should be pretty self-evident how it works.
There's a README inside the tarball. Among other things, it mentions that you need:
* A working SMF installation.
* A MySQL database. It'll work with other databases but may need some changes.
* Understanding of MySQL.
* Understanding of how to edit PHP code.
* Understanding of how to edit HTML (for the templates).
It's a semi-technical install; it will not work for you out of the box, but the tuning is within range of anyone who knows how to create MySQL databases and modify constants in PHP.
The core framework is Code Igniter, which I heartily recommend to anyone doing PHP web apps.