Where may one find discount home gyms available for purchase?

Check your local and surrounding areas within driving range on Craigslist in the sporting section. You shouldn't have any trouble finding weights, a few bars, etc. for a quarter of what it would cost at a store. Whatever you can't find on craigslist you can look around yard sales for or just buy the remaining things at Walmart or somewhere similar as they sell gym equipment for cheap.

You should be able to find a few bars, about 200lbs of weight, and a bench for under $100 on craigslist.