How to contribute to site?

I am looking at https://pgweb.postgresql.org and don't see any pointers on 
how one contributes to the pg doc project.

Also checked http://wiki.postgresql.org/wiki/Developer_FAQ and the wiki in 
general.

Any URLs or any pointers on how to contribute?
I particular I want to provide examples for this page:
http://www.postgresql.org/docs/8.3/interactive/ddl-partitioning.html

I spent the better part of an afternoon figuring out how to make a dynamic 
function to send data to the proper partition.

I recall there was a presentation in a PDF that had a sample, but could not 
find it anymore. Neither could find any examples.

Figure I could share what I have so others have a starting point when doing 
partitions.