Hi LaDreka,
West Chester has a local paper that comes out on Thursday that will have listings of (usually) dozens of garage sales in West Chester and the Mason area. It used to be thrown at the end of the drive way when I lived in West Chester a couple of years ago.
I imagine you are asking about the flea markets there off 75 at exit 63? It is people who have rented booths, inside and in nice weather outside and are selling "stuff". Some of it is good "stuff" and some of it is junk. Some of it is over priced and sometimes you can get a good deal. You are pretty much expected to haggle or barter with the person for a better price. My best advice is to know what it is you are looking for so you don't get ripped off in the process because the bottom line is not everybody is honest. Sometimes the flea markets are good entertainent on bad weather days since they are indoors. They may have live music, plenty of junk food, it is fun to people watch and you never know when you might really find an excellent deal if you are seriously looking.
I moved here from Michigan years ago. I currently live in Mason which is just east of West Chester. If you want to get together drop me a line privately and let's see what we can do. I love meeting new people.
J.