The Snare/Epilog open source agents will get you part of the way there; they'll handle the log forwarding side for you. They're coded over the ditch in Oz.
Kiwi syslog might be another step in the process; locally made and supported in NZ; it'll manage the collection side of things, but not the analysis.
From there... sorry - I only have commercial stuff to suggest for the analysis side, so I'll let others bring up some options.
[Disclaimer: I'm a snare developer, so take comments in that context]