The tenth edition of this introduction to the theory and practice of welding processes and their applications has been completely up-to-dated, including a new chapter on the welding of plastics, and new sections on the welding of duplex stainless steel and air plasma cutting.
Now I can't comment on the accuracy of the information in this book or whether it is still valid or applicable but I did find it surprisingly easy to read and rather enlightening, I hadn't realised there was so much involved in welding. This certainly seems to be a comprehensive look at the theory and practice of welding and has clear instructions and practice exercises that can be undertaken before working on particular projects. I'll be honest, I don't think I'm in a position to try it myself but were I more practically capable then I definitely would use this.