I've recently developed an interest in historical exonumia pertaining to my hometown of Benicia, CA. Exhaustive research tells me at least several dozen known merchant, military tokens and locally produced commemorative items exist. Many are quite elusive but I've had some limited success on Ebay. For those that have specific exomunismatic (is that even a word?) interests, where are you finding what you're looking for?
What I do find, which hasn't been much, is off Ebay. The correct term is Exonumia. British call it Paranumismatica.
My Florida LCS gets things like that with old accumulations of silver coins. He throws them in a box to be picked by anyone interested. About $2/handful. I let him see any foreign silver but he always says just keep it with the handful.
eBay is the most likely place to find what you want. If you want rare tokens you'll need either lots of luck or lots of patience. Coin shops and coin shows are sometimes successful. Especially if the shop or show is in the area your target token(s) were originally used. Buying duplicates from someone who collects the same kinds of tokens as you is a great way of finding what you want, but those connections can be difficult to make. Also local antique shops. Some of the greatest finds come from those.
