Q:

Scavenging metal resources in post-apocalypse after 100 years

This is another question for a setting I mentioned in previous questions (currency, ammo). The setting is:
It's happening in post-apocalyptic SE Europe (Balkans specifically), about 60-80 years from now. Strange genetic disease wiped out a large portion of humanity in a matter of a few years. The rest of humanity killed and pillaged each other until our numbers were indeed few. The surviving humans have a genetic disorder which makes pregnancy harder.
Nature is, for an unknown reason to people, thriving, mutating, being more hostile to people. Wild plants are growing slightly faster, predators are bigger, stronger, smarter and more dangerous. Besides that, there are the "wild ones", feral humans that live like animals. All this has made trade and traveling quite hard, but not impossible.
Cities are overgrown with plants, wildlife moved in, forests are bigger.
People are living in smaller independent settlements (100-400 people), scattered, fortified. Bandits and roamers are common. Settlements are somewhat self-sustaining, but still need to trade with each other, because resources they have access to are different. There is one specific settlement in the area, based around the old University, which harbors and preserves "old" technology and knowledge, and uses that knowledge as a commodity, fixing and making technological stuff for other settlements in exchange for food, protection, and so on.. There is no unified government or force, and all attempts to form one have failed.
Technology is somewhat preserved, but only partially. For example, people know what solar panels are, or that somehow electricity can be produced from a windmill, but only a very few people actually know how it works and the science behind it. 
The area I'm looking at is around what used to be a half million city, with smaller towns around it. Now its a mix of concrete and plant jungle, lots of buildings are decayed, flora found a way in most of the places.
My QUESTIONS are these: 
There are people who are looters/scavengers, they take their chances against hostile wildlife and bandits to roam the ruins of the cities and towns for the search of rare materials used by the remaining technology. 
From which items would the people get next metals:  

Platinum
Aluminium
copper
lead
iron (pure)
tungsten
zinc
tin
maybe some really useful elements i am missing (feel free to add).

What household/industrial items can be salvaged to get those metals out of them in decent quantities, and please keep in mind of the decay - a hundred years have passed since the world stopped functioning.
For example, Platinum can be found in catalytic converters in cars, copper from electrical wiring etc.
Basically, I am looking for various resources needed to make things like lightbulbs, batteries (for storing electricity harvested with wind or water turbines), specialized tools, ammo, firearms. 

A:

Platinum: Platinum could theoretically be extracted from the catalytic converters of wrecked cars. 
Aluminum: Literally everywhere. You could find literal tons of the stuff buried in rubble of cities or in the engine blocks and pistons of car wreckage strung across hundreds of miles of former highways.
Copper: There are millions of miles of the stuff in fallen power lines, pipes in wrecked buildings, wiring in wrecked buildings, etc etc. 
Lead: Car batteries each contain 15 to 20 pounds of the stuff. 
Iron: a lot of car Engine blocks are made of cast-iron. Why bother with iron when there are literally tons of high grade steel laying everywhere?
Tungsten: Could be found in heating elements of heating furnaces, a lot of welding equipment is made out of it, if somebody were to scrounge around former industrial sites and construction sites you could find stuff made out of it laying around. 
Zinc: approximatley 17% of modern consumer products incorporate die-cast zinc in some form, and tons of it would be laying around in alloyed form in stuff like kitchen faucets or assorted other objects.
Tin: Not really used in pure form for much of anything. Its mostly used today for alloying, most main uses for pure tin have been replaced by aluminum alloys. Tin is everywhere but is almost always going to be an ingredient in an alloy. Purest sources would be spools of solder, but that would also be an alloy with antimony and lead.  
Basic point being, if a large portion of the population died off there would be a ridiculous surplus of pretty much everything laying around waiting to be identified and used. Your specialized scavengers would probably be special more for their ability to identify what alloys where what and what components were made out of what materials than for their ability to gather them. Free resources would simply be scattered from hell to breakfast waiting for somebody to identify their potential uses. Unless its really REALLY dangerous to leave a settlement finding resources would be laughably easy. 

