I'm baffled as to why this seems to be the only decent "open-source" (if not community-developed) solution, but after a few research efforts over the last several years, I've repeatedly come up with NXLog as the best option for handling Windows event logs in a primarily *nix-based environment.
NXLog has a special input module for this purpose called im_msvistalog. I've been using this with NXLog Community Edition and it works well so far. (FYI, I'm shipping Windows logs directly to Solr.)
I presume that there just aren't that many people using tools of this flavor (i.e., Apache Flume, Solr, Java, typically Linux-based tools) for handling Windows event logs. :-) I'd like to know why if anyone cares to chime in. I guess people with Windows infrastructure they care about will just have something like a centralized Windows Event Viewer that operates as a syslog daemon would in a *nix environment?
If this solution doesn't work for you, you can also try querying the Windows event logs using the Windows Events Command Line Utility. I haven't yet had to resort to that since everything I've needed has been available using that NXLog input module I mentioned above.