hmmmm....I just got done putting together a computer, which involved some welding, as well as assembling an electronic kit (the clock).
http://www.selectric.org/ibmpc/atxpc.html
Several years ago I built a "homebrew" Nixie clock, but I have sources for old parts, which you may not have available.
http://www.selectric.org/nixie/index.html (scroll down to the bottom of the page).
You might not want to get into this high voltage stuff until you understand the necessary safety precautions.
When I was young, we had Heathkits available, although we never had enough money to buy them ourselves. Dad bought a TV kit that my brothers and I put together when we were in Jr. High, I still have the TV, it still works.
My guess is that getting into electronics now, is not the same as it used to be....everything now is so small! All the ICs are surface mount, etc. And vacuum tubes are pretty much gone, even as displays.