Resources for learning videography?
There is this, aimed specifically at the GH3: http://www.eoshd.com/the-eoshd-panasonic-gh3-shooters-guide-book I have it and it's very good IMO.
Plus there is a video forum here http://www.dpreview.com/forums/1045 where you can probably get lots of advice and other sources.
Finally, here are some things I've bookmarked:
that are also GH3 specific.