The Low Level Radiation Campaign has issued a new bulletin at http://www.llrc.org.
Now that there has been a major explosion in Fukushima Reactor 3 the pressing need is for monitoring of radiation levels. We are not aware of any coordinated effort to track the fallout or to pull together Geiger Counter readings.
LLRC has monitoring stations in Riga and Aberystwyth (Wales). We are prepared to collect and publish readings sent by other volunteers. Details are on the web site.