Try everything, at least see it done. Get involved with a local ABANA chapter or some other organization to talk with others about blacksmithing, metalworking, welding etc.
Stay involved with a group and work at the craft. Ask people for help, work on a demo at the meetings or public demos and search the Internet for more info, read, read, read. Check the libraries for title that might fit you interest. It may be hard to find every book, but with a little time and trial you can find lots of books that have something to help you out.
I found that I had nothing to show for my hobby, when people asked what I made. I was giving everything way and not keeping anything, let alone keeping the best of the projects. I finally decide that when I make something, I would make 2 or three and keep the best one, then make the others gifts or for sell etc. Always work for yourself along the way, don't get left out.
Similarly, I was not getting anything built or repaired in my shop. To complicate things I can't spend a great deal of time working on iron so my time can't be wasted with broken equipment. I try to fix a tool or motor or the like, make a new tool etc. every time I work on anything. Sometimes my entire "session" will be making a new tool (take the Circular Saw to Cutoff Saw project for example). What I have seen is that I have lots of tools that work and lots of projects that I have finished too. (Granted there are lots of unfinished stuff just laying around, but things are getting done. ;-)
Buy the best tools that you can afford and then some. I have decided that when I buy something new, I want something that will last the rest of my life. I can't be buying a new angle grinder every few months (even if they are $20 a piece). Even though I don't be the top of the line, I buy a good brand and a model that exceeds what I need, so I won't be breaking it halfway through the first project (an experience with a $20 angle grinder and a 0.75” thick truck brake drum forge).
As for consumables, I buy cutting wheels, sanding disks, sand paper, drill bits, etc when I see it for a good price and not when I need it ... before I run out. I may not use lots of them, but when I am in the crunch I will have new replacement blades, cutting tips, spark igniter flints, hose couplings, screws, nuts, washers etc. I try to have the essentials to get by without having to spend my work time, running to the store. Especially then not every hardware store had Lincoln Welder or Victor Torch parts. That said I have purchased duplicates and even triplicates of things like torch handles, gauges, etc. Things that we a good price when I found them and are standing by so I can keep working without a break down that stops everything. E.g. I need to buy a $100 gauge to finish a $2 project and the gauge store is not open for 3 days and it is in the next county ... or some such scenario. Not to mention that you have these tools at a job sight or in my case a blacksmithing meeting or maybe worse a conference or workshop. A gauge malfunction might be rare, but have it happen while the paid demonstrator is heating away ... well I might be over doing it here. Cover you options and hedge your bets.
I break a rule or at least advice from others. I have had real good luck buying used. I check it out and most second hand stores (Pronounced Pawn Shops) will warranty their welders, torches etc. to work or bring them back. I have bought some torches and gauges that did not work leaked, etc. I didn't pay much for those and expected that there might be problems. I get them repaired with new parts for a reasonable fee and on the whole I come out spending less money for all of them used and repaired, than only a few tools would have cost new. Further having extras might some day allow me to loan then out or leave them on a job sight and still be able to work in my shop.
As for tanks ... this is my philosophy, not my advice ... I buy compressed gas tank used and consider that I am going to turn them in to get them filled and the gas shop will keep me safe. That has not blown me up ... yet. If in doubt ... don't. If it looks too good to be true walk away. Most important is to know what you are looking for and what you are looking at and make a good decision, not one in haste or in a bind. The most important safety device you have is your brain; make sure you have it engaged in you shop and when you shop.
Sure we would all like a 600 Amp super arc plus welder, AC/DC, MIG, TIG, STICK, PULSE and GOUGE with air compressor and espresso machine mega-combo, but what I do have is good stuff and does more than what I need.
Don't throw anything away. Well, throw the real junk away, if you can determine what to throw away. Otherwise do as the old timers and have stuff stacked up everywhere. I throw away the pieces that I know aren't going to be useful or that just aren't the kind of thing that I will be working. Otherwise I might use it, or give it away. Or possibly it might end up in a tailgate sale ... or some anthropologist will dig it up in the year 3510 and won't he be confused.
Don't we afraid to ask for help and please don't be afraid to share what you know. Everyone can learn something and can teach someone something. If we as artist blacksmiths do not keep the art alive who will do it. We should not stomp off as if to war, but have a passion for our work and propagate the knowledge passed down to us.
Share, share, share.
2000-2004+ Vice President
North Texas Blacksmiths Association