For information about.......
Civil Defense - www.civildefensemuseum.com
Nuclear weapons - www.nuclearweaponsarchive.com
Fusion - www.Fusor.net
Atomic collecting- Health Physics Instrumentation Museum Directory
Element Collecting, including radioactive ones http://www.theodoregray.com/PeriodicTable/ There is also a link some where there to order a great book on all things radioactive called Living with Radiation
http://www.radiochemistry.org/
To buy nuclear related stuff
www.unitednuclear.com Awesome service and one of a kind items!
www.spectrumtechniques.com/ Awesome service and items!
If you need dosimetry or you've got a somewhat larger budget for used rad instrumentation try
http://www.chpconsultants.com/
They are wonderfully nice people and thats where I get my TLD dosimetry from. Some of the cheapest prices anywhere and have CHPs to help out. The prices for used radiation instruments is a little higher than what you would pay on eBay, but its 100% working if you don't want to gamble or fix anything. They are very good to deal with if you are an amateur since they are not a large corporation and they have some of the cheapest prices on dosimetry avaliable, plus advice to back it up.
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