One of the best places to get detailed information on welding, considering any medium, is the Newsgroup / "bulletin board" sci.engr.joining.welding. It's archived on "Google" at Google Groups and usually you want to click on "Search only in sci.engr.joining.welding".
To post questions and generally keep up to date with sci.engr.joining.welding, you will want to "subscribe" to it from you Internet Service Provider's news-server (NNTP server).
This was a big endeavour for me. I attended vocational welding courses over a five year period.
Welding process training - oxy-acetylene, SMA, TIG, MIG and a bit of pipe-welding.
TIG welding: feeding filler wire - technique for manual TIG welding (has movies).
Note this is continuously feeding filler for sheet-metal thicknesses - not the cyclic "stack of dimes" method used for large TIG welds.
Welding equipment I have used.
Mixed miscellaneous stuff on welding.
If you weld, you often also want to oxy-acetylene cut. So here is the
method I use to
set an oxy-cutting torch.
It does not use pressure gauge readings.
The article starts with methods to mark out "black" steel - steel as-rolled with oxide on surface. Using soapstone, rules and squares.
Is the current "preferred" approach to weld metallurgical qualification, ISO15614, continuing to work well? Is it time for a re-think? Here is an alternative new proposal taking the currently less-used very-restricted-application ISO15610 approach and making the ISO15610 approach the new preference for most welding fabrication.