Below are several great sites to worth visiting:

http://www.mircscripts.org

http://www.scriptsdb.org (French)
Finally, to make your script file conform to the plugin system of Zion, take a look at the Tag plugin. (installed with z3)
The top 36 lines are the conforming codes, therefore needed. You can modify what happens in each procedure but the general layout needs to stay that way.
As for file naming convention & folders placement, take a look at this post:
http://forum.zinc.sg/viewtopic.php?t=30