Valve data includes various types which may be used in the Racal RA17L HF receiver.
http://www.pamandandy.demon.co.uk/valves/index.html
Various types of time keeping devices made with Nixie tubes and Nixie tube like componenets.
http://www.nixieclocks.de/
Vacuum tube resources for students and more advanced users.Everything from fundamental techniques to SPICE simulation.
http://www.ee.ualberta.ca/~schmaus/elect/tdex.html
Information on the 6L6 look-alike, and where to get the last remaining tubes.
http://elektronenroehren.de/avvt/html/avvtclub/
Brent Jessee Recording Tube Sales and information. Plenty of data and articles here too.
http://www.audiotubes.com/
Audio tube amplifier project. European tube number guide. Links to other tube sites.
http://www.radiopistoia.com
Valve radios, and vintage electronics. From Australia. Includes some tube data from down under.
http://www.geocities.com/CapeCanaveral/Hall/1359/
Portable tube tester from the United Kingdom. Includes other tube tester information too.
http://www.duncanamps.com/technical/ct160.html