You can also browse the following online resources:
And don’t forget about the rsyslog mailing list. If you are interested in the “backstage”, you may find Rainer‘s blog an interesting read (filter on syslog and rsyslog tags). Or meet Rainer Gerhards at Facebook or Google+. If you would like to use rsyslog source code inside your open source project, you can do that without any restriction as long as your license is GPLv3 compatible. If your license is incompatible to GPLv3, you may even be still permitted to use rsyslog source code. However, then you need to look at the way rsyslog is licensed.
Feedback is always welcome, but if you have a support question, please do not mail Rainer directly (why not?) - use the rsyslog mailing list or rsyslog forum instead.