You kind of have to decide what you are going to do I think to narrow down the search.
Are you going to build lamps and then are you going to sell them of just for yourself. I might want to suggest doing a few drawings and determine if any type of parts jump out at you. I happen to use large oil or water valves, pieces of sheet metal and metal barn type shades. Do you want to know why? It was because I found a bunch of all of those about the same time and started to work. They fit together.
Now do I have a stock of gears (large and small) and wheels (large and small) and a ton of parts to gas meters, all kinds of amp meters and pressure meters hoses wires locks keys cables old tools lamp parts …I sure do but those are for later and to add some little things to the lamps.
Here is a list of things I have found and not paid a whole lot for these things:
It is free when railroads do repairs they rarely take the old parts back with them and there is a pile of stuff just left at collection points for them to pick up later…later rarely comes. Large nuts, metal banding, tie cleats, and odd pieces of really nicely rusted metal. Just take a walk down some older tracks you will start to tune your eyes to sight in on things and then find some stuff. Key an eye on the tracks both in front and behind and please do not wear headphones for your MP3 player or you many never get started in the industrial art world.
You had better know the land owner here Oil fields repair dudes do pretty much the same things as Rail Road people. After the repair stuff just lays there because it is large and heavy and broken too much to haul back and it just lays there.
Estate sales and garage sales a bit hit and miss. If there is going to be some garage stuff you have a great chance.
Your best friends stuff
Steal his or her stuff (see above) (just kidding please ask them)
A light or heavy industrial area that is on its 2nd generation of tenants.
A Grain chute for loading trains maybe the building was built for a different kind of business and there are things just lying around maybe a former tenant left stuff lying around.
Anytime a business gets torn down
Metal scrappers before they turn it in get to know some of these guys and what you will buy. You are bound to give them better money than a yard will.
Metal scrap yards see if you can go through these and pay the night guard or whatever you work out but be advised you getting hurt crawling around in their metal piles will be a hurdle you need to get passed.
O.K. it is a long shot.
Used stuff stores anything is possible here.
Dollar tree light globes made from cheap glasses
Retail all kinds of stores antique stores junk shops ….
Home depot connectors bare copper wire, wood, piping,
Craigslist need I say anything here sometimes the free stuff is the best for what you are looking for.
Pianos, adding machines, old printers, gas meters, old sewing machines so many parts I can nor start to mention them all do not pay more than 10 bucks for an adding machine, make sure gas meters (the ones off of homes) are older the gears are brass not aluminum, older sewing machines that do not work 10 bucks tops from Craigslist or yard sales old printers (not the ones made since 1985. The old offset types.
Well there you go there are plenty of places from which to gather parts to build with. This should help to Get Started in the Industrial Art World.
I will talk about other ways a little later for you.