Not only gives you map, but a link for the text version, but also a link for interpreting the data.
real time stations across US
real time station in Southern California
black and white graphical data, not mapped, very precise
Resource guides and information:
for telling the difference between the ion-chamber kind and the other kind
Primary News Sources
if it isn't here world governments won't admit it (but it may still be true)
Japan official press releases (PDFs) in english
if it is not here Japanese government won't admit it (but it may still be true)
Secondary News Sources that I go to first in this regard
all the news that used to be on Florida Oil Spill Law, now on its own site
Be seeing you.