Oh, I'm an expert on blue mason jars since I'm using them for the centerpieces in my wedding!If you want the large jars, check out the flea market at the state fair grounds (if you're in the Raleigh area). Or I think any flea market in any area will be a good place as well. I've gotten a total of 5 large blue mason jars there over the past couple weekends. They range from $5 - $20+ depending on the rarity & condition. I haven't paid more than $10 for any jar. For smaller sized jars,I plan on trying THIS tutorial to make my own. It's a heck of a lot cheaper to buy a case of plain jars and paint them then it is to buy antique blue ones. Mix them in with the real vintage ones and no one will be able to tell!