The Bioware forums for NWN are down it seems. But you can always use the Wayback Machine to reach older content.
http://web.archive.org/web/20160916163446/https://forum.bioware.com/topic/157227-resources-for-nwn-1-builders-toolset/
The nwn wikia page is decent. Here's some tips on making your first module.
http://nwn.wikia.com/wiki/Your_first_module