There is no real need to buy them new (unless you are canning), just take the effort to see what is underneath the paper label of your favorite jarred pasta sauce, pesto or salad dressing.
I use my collection in lots of ways. Smaller jars are an easy way to mix and store the ingredients for homemade salad dressings, spice mixes and instant pudding. Use a jar for anything with the directions "Add liquid and stir" and with a few shakes you have saved dirty dishes. I also use mine to mix flour with broth for gravy, a few vigorous shakes to mix eliminates flour lumps. Any of the jars can be used for storing or transporting sauces or liquids, or for dry food storage in the pantry.
But these jars need not stay hidden in the cabinet or pantry, especially the ones with the raised glass labels. I pull them out to use as easy vases for cut flowers or paperwhites, to hold silverware at an outdoor picnic or as a hurricane candle holder for pillars or votives. These uses can also add a nice element of personal style to a bookcase or centerpiece.
Most of the jars have a thick rounded construct and a collection could also serve an eclectic set of drinking glasses. I think the perfect beverage a choice for these is a glass of sweet tea or lemonade enjoyed on the front porch.
(1) Square (no label) jar used for dog treats; (2) A crafe (glass label "Made in 1896") as a vase for hydrangeas; (3) A "Ball Mason" jar for dry storage of kidney beans; (4) Round pasta sauce (no label) jar holding silverware for a BBQ; (5) A "Naturally Fresh" glass labeled jar used as a candle holder--how wonderful would several of these be as lanterns hanging in the trees at a garden party; (6) Round salsa jar filled with refreshing lemonade and ice; (7) Small jar (no label) ready for catching lightening bugs:); (8) A pesto jar (glass label "Atlas Mason") as a small bud vase.
Once you collect a few jars take a look around your home. Is there something that you can store, display, gift, entertain or cook with using a mason jar? I may take a few to my office desk for pen and pencil storage for a little "home away from home".