Packaging mostly happens for the openSUSE distribution. The distribution tries to form out of the vast mosaic of open source projects a coherent product. Packaging is the means to form the projects and therefore packaging for the openSUSE distribution has a lot of rules. We adhere to the general Linux Standard Base (LSB) that tries to reduce the differences between individual Linux distributions. In accordance with the LSB specification we also follow the Linux Filesystem Hierarchy Standard (FHS) which is a reference on how to manage a Linux filesystem hierarchy. Additional to these general rules every Linux distribution follows we have our own set - the openSUSE packaging guidelines which regulate all the nitty gritty details of packaging for the openSUSE distributions.
There are two very extensive guides for the RPM and Dpkg package formats that will give you and introduction.
The RPM-Guide by Eric Foster-Johnson and the Debian New Maintainers' Guide. We will not try to duplicate them but concentrate on the openSUSE tools and workflows which means all our documentation expects that you know your way around the package formats.
All packaging happens in the openSUSE Build Service, our open and complete distribution development platform. Therefore the most important piece of documentation for you as a packager is the Build Service Tutorial. Its very RPM centric so we have another document describing Debian builds. You can also have a look at the Tips and Tricks and, if you are interested to build for more than one distribution, at the Cross Distribution Howto.