The Global Network of Investigative Journalists is a comprehensive site, with lots of links to other networks and useful tools and tips: Global Investigative Journalism Network
Journalism Fund is a useful European site: http://www.journalismfund.eu/?page=13&detail=19
A site for teachers of investigative journalism: http://ijec.org/
The Pacific Journalism Review is Oceania’s premier academic journal on journalism: http://www.pmc.aut.ac.nz/. In May 2014 it published a special issue on investigative journalism trends in the region: www.pjreview.info