My personal experience:
I took a class, learned the basics, but not enough to be good.
I'm still learning, but I've learned more from practicing, and posting welds up online, and getting feedback from folks who know what they are doing.
I'm considering taking a class to get certified at some point, but for just doing your own stuff, I would recommend spending the money on some nice equipment rather than a class.
Aside from the welder, a nice, quality (not HF) auto darkening helmet is well worth the coin if you plan to weld a lot. I had an HF one for a while, and while building my various rigs, I began to notice spots and issues with my eyes. Turns out, the reaction time on those HF helmets is slow, and the Eye Doctor said I was starting to damage my eye balls.
Got the new helmet, and problem has gone away.
Alternatively, the cheap option is to get a good shade regular helmet, and learn to do it that way. I hate those, but some folks swear by em, and they are more than adequate to protect your eyes.
And, John, I'm curious why you recommend the gas set up? We learned it in my course, but I've never been a fan, as it requires way too much heat to go into things, and warps the hell outta everything I've every tried to weld that way. I've only ever used a torch regularly to heat and bend stuff. Welding with it always took too long, and made a mess.
By the way, I'm not arguing with you, but rather, I want to hear your reasoning, since you actually do this for a living.
Baby Beast 2- 1999 4Runner SR5
Baby Beast -1987 4Runner SR5-Gone, but not forgotten