Here, people are buying all the rusty tin that they can to decorate the ceilings of their homes. Craigslist will have it from time to time, but for best results, it's better to just buy it and stain it yourself to get that look. There are dozens on websites with different formulas on how to do this. I think bleach, vinegar and rust are used, but I would do a search first and read up on it. The results that I've seen have looked pretty realistic.