The Debian Package Tracker
Introduction
The Debian Package Tracker is a set of services tailored to distribution developers, package maintainers, and anybody who might have to interact with those people (upstream developers, bug reporters, advanced users, etc). It lets you follow almost everything related to the life of a package (or of a set of packages).
It's hosted on http://tracker.debian.org.
Contribute to the Package Tracker
The software powering the Debian Package Tracker is called "Distro Tracker". Have a look at the "Contributing" section of its documentation: https://tracker.debian.org/docs/contributing.html
It answers everything!
Documentation
Here it is: http://tracker.debian.org/docs/
The documentation is updated once a day and matches what is deployed on tracker.debian.org.
Otherwise you can generate the documentation yourself by doing "make html" in the docs subdirectory of the distro-tracker git repository.
Questions ?
Ask on debian-qa@lists.debian.org or in the #debian-qa IRC channel. Thank you!