There is a lot of info in the in the library section:
http://www.project1999.org/forums/forumdisplay.php?f=2
I personally use the game companion a lot:
http://www.thesilversandbox.net/p1999/main.php
There's also a Wiki which is still being updated and a great resource:
http://moestaverne.com/p1999wiki/index.php/Main_Page
Last but not least learn to use this:
http://www.archive.org/web/web.php
When doing your searches through the archives remember that classic EQ is 1999-2001 (with 2001 also including some Luclin changes which you want to ignore).