I want to take a moment to start from the beginning.
What are Coupons?
Coupons are essentially a promissory note from the manufacturer to the retailer. Once they are in your possession they are your property until you exchange them for products.
When I walk out of Publix with a cartful of groceries (or two ;) ) in which I paid $4 cash, that looks like I got something for free. I assure you, this is not the case. In my transaction I exchanged several hundred dollars worth of promissory notes for my items. These notes will be sent to a coupon clearinghouse to count and sort. Then a few more things happen (I'll spare you the gory details) and the end result is the manufacturer reimburses the retailer face value of the coupon plus $.08 per coupon for handling.
The trick is to find a store with a Manager who understands this. Many of them look at you and think, look at all that stuff that woman got for free. (And they get jealous, or mad, or something...) But once you find a store with a manger who understands how coupons really work, I recommend you shop there. And nowhere else.
Types of coupons.
There are several types of coupons, and these are released in different venues. I've covered the places to find coupons, papers, tearpads, blinkies, etc. I now want to talk about types.
The main type of coupon is a manufacturer's coupon. A manufacturer's coupon (or manuq, or mq for short) is a coupon released by the manufacturer to be used by the consumer at a retail outlet. A manufacturer puts out coupons to encourage purchase of specific products. Often these are new products on the market- so that people try these items at a discount, love them, and continue buying them. Coupons from manufacturers are generally released seasonally. You're not going to find soup coupons in the summer or charcoal coupons in the winter.
Store coupons. Store coupons are coupons that are store specific. The way these work is that a big-wig at the Manufacturer gets together with a big-wig at the retailer. They work up a deal where the store puts out a coupon specific to that item at only their store. In return, the retailer gets... something. The "something" will depend on the deal. It might be 50% of face value of coupon turned in. It might be a specific amount of money. Whatever the deal, the store generally does get reimbursed something for the store coupons used.
Coupon usage will differ depending on the store you are shopping at, but there are a few steadfast rules.
1) You may only use one Manufacturer coupon per item. Period. Ever. If your coupon states "Save $1 on 2 Ragu pasta sauces" then that coupon applies to two jars of sauce. You may not buy two jars of sauce and use one $1/2 coupon and also a fifty cents off one coupon. These may have different values, but the rule of one coupon per item applies. The coupon that is "off of two" applies to both items.
2) Never, EVER photocopy coupons. It is illegal. Period.
Then we move into the other info that will vary by store.
Many stores will allow "stacking" of coupons. This means you may use one manufacturer coupon and one store coupon per item. This is where you get the best deals.
Some stores that allow this? Publix, Target, Kroger, Whole Foods, Food Lion, Walgreens, Rite Aid, CVS.
When stacking, read the fine print on coupons to make sure the coupons do not exclude this usage.
Some stores will accept competitor's coupons. Publix. Some Kroger stores (ask at your store). Some Wal-Mart stores.
If your store accepts competitor coupons, ask Customer Service who that store considers a competitor- you will find out it varies by store, but it is worth asking.