From J.W. Kwang in Korea
http://tubesall.hihome.com/tube.htm
How to use them and how they work. One of the more accurate vacuum tube FAQs on the net.
http://shay.ecn.purdue.edu/~busenitz/vac.html
Interesting, large transmitting tube information, by AB0CW, Mark Dittmar.
http://www.qsl.net/ab0cw/861_power.htm
Tube datasheets on-line.
http://www.drtube.com/tubedata.htm
Photos and project notes for the Russian GM100 Tube.
http://www.vt52.com/diy/myprojects/amps/gm100/gm100.htm
Tube tester manuals online from BAMA.
http://bama.sbc.edu/military.htm
Great WW2 era RF transmitting and audio power tube.
http://www.rod.beavon.clara.net/807.htm
A great resource for tube theory and operation. Quite a bit of history also.
http://www.tubecollectors.org/