Glassblowing tools:
Wale Apparatus - Torches, graphite tools, oxygen generators, etc. This is where I purchased all my glassblowing tools. They sell a scientific glassblowing kit, and are flexible enough that they allow you to add/remove items and retain the 10% kit discount. They also supply borosilicate glass tubing and rod.
Glass:
Voltarc Masonlite - Where I got lead glass tubing. The tubing comes as 50lbs boxes (except for 25mm tubing, which comes in 30lbs boxes). They do not sell directly to individuals, so I had to purchase it through a neon sign supplier (but picked it up at the factory in Orange, CT). The glass itself originates from Osram Sylvania in Kentucky.
Wire (glass to metal seals, filaments, supports):
ESPI Metals - A source I used for kovar wire. They do not sell to individuals, so you must order through a company or educational institution.
JLC Electromet - Dumet, NiFe, nickel
MWS Wire Industries - Supplies Dumet, nickel, tungsten, molybdenum, platinum, etc. Their quote to me for 50 feet of Dumet (minimum quantity) was on the pricey side.
Classes:
Scientific glassblowing is a dying art in the United States. The only school in the US to offer a degree in scientific glasswork is Salem Community College. Basic classes are hard to come by, especially as universities (unwisely) close their glass labs for budget cuts. I was fortunate enough to be able to take an introductory course by glassblower Daryl Smith at the Yale Scientific Glassblowing Lab (there are no intermediate level courses). The course is offered to a maximum of 6 students per class (sometimes with 2 class sections per semester), and chemistry graduate students have first priority for getting these spots.
Scientific glassblowing links:
The Scientific Glassblowing Learning Center - Tutorials by Joseph W. Walas, retired East Carolina University scientific glassblower.
Links to other homemade vacuum electronic devices:
The following are links to every site I could find on the internet containing homemade vacuum electrical devices (lamps, diodes, triodes, CRT's...). If you know of any more, let me know!
http://www.youtube.com/user/glasslinger/videos/ - There are a number of very useful and detailed videos by Ron Soyland on YouTube under the username "glasslinger", where he demonstrates and explains the construction of various vacuum tubes and glassblowing techniques.
http://paillard.claude.free.fr/ (French) - Contains an excellent 17 minute video showing the steps Claude Paillard uses to make his own triodes. The site also contains what looks to be a lot of useful information, so it's probably great if you speak French, however I find it hard to understand much of the site using Google translate.
http://www.tubedevices.com/alek/ (Polish) - Aleksander Zawada makes number of handmade vacuum devices, including diodes, triodes, tetrodes, ion gauges, neon and nixie tubes, Crookes tubes and more. The site is mostly interesting to look at, but unfortunately not much information is given on how anything is made. The site is also a bit disorganized and hard to navigate, but still worth browsing. There is an English version of the site, but it is missing some of the content of the Polish version, and also has a few broken links, so I prefer to navigate the Polish site within Google translate.
http://www.teralab.co.uk/Glass_Blowing/Glass_Blowing_Menu.htm - After learning some basic scientific glassblowing through reading a few books and experimentation, Robert Hunt describes a number of techniques he uses to produce a number of incandescent lamps, a diode, triode, photocell, CRT, and a few other devices. He also describes the materials used, and has a few videos demonstrating fabrication.
http://www.oldatheart.co.uk/hometriode.html - A homemade triode by Gerry Wells, curator of The British Vintage Wireless and Television Museum.
http://home.earthlink.net/~lenyr/ and http://www.sparkbangbuzz.com/ - While he uses absolutely no glassblowing (none of the devices would work without a continuously running vacuum pump), Nyle Steiner makes his own crude (but functional) diode, triode and a number of CRT's. The rest of the projects on his site are also very interesting.
http://www.hpfriedrichs.com/bks-ioa.htm - H. P. Friedrichs writes about his homemade triodes, among other types of amplifiers, in his book "Instruments of Amplification". I have not read the book, but from the photo gallery on his website it looks like the triodes are in the same style as Nyle Steiner, not utilizing any glassblowing and requiring a running vacuum pump be connected in order for the triodes to function.
http://imajeenyus.com/vacuum/index.shtml - Lindsay R. Wilson explains how he makes Houskeeper seals, and demonstrates a thermionic diode under a bell jar and a Panaplex display in a jam jar.
http://www.toptinkers.com/ - Oliver Snowdon shows several attempts at making diodes, having some success at the end.
http://www.incandescentsculpture.com/ - While more artistic than scientific, this site displays a number of incandescent lamps hand-blown by artist Dylan Kehde Roelofs (many of which are for sale).