I started couponing in May, and last month saved almost $250. I live in a small town, we have a Wal-Mart, Food Lion, and small indy grocery. The great thing about Wal-Mart is they price match, and will price match from the two closest (30 min) cities away. I buy 3 papers each week, and go through all the grocery stores Wal-Mart will match on CouponMom. As I make a list, I list all the things I'm price-matching from a certain store together, and then use a black sharpie to circle the items I'm matching in the flier. When I get to the register, I put all the price-matching items together, and the cashier and I go through it item by item. Because I'm so organized, the cashiers are usually very nice about it! Something else to keep in mind, Food Lion is usually the most expensive grocery around here, but they do a LOT of BOGO, and when something is bogo, it's always cheaper to get two there than it would be normal priced somewhere else. They also do a "meal deal" where you buy usually one or two of an entree and get certain items free. I save a ton by using coupons on the free items. I never walk out of there saving less than 50%, which I consider great since that includes meat, produce and dairy that are hard to find coupons for!
I also do CVS, there are a lot of sites that post $5/$10 scenarios to make the most of the ECB deals and tell you what coupons to use. My faves are simplycvsshopping, southern savers, and kingdomfirstmom. (All dot coms.) Kingdomfirstmom actually posts her $5 scenario, and then lets others do the same. Usually by 10am Sun there are at least 5 different sites linked, so you can choose the one with the items you need. I found the scenarios very helpful when I was starting out, and though I've planned a couple of my own now, I still check them weekly. So far my best trip had me walking out with 92% saved, and I now have a great stockpile of shampoo, conditioner, feminine hygiene items, toothpaste, toothbrushes, deodorant, and razors!
It does take some time, I would say I spend 2-4 hours on Sunday planning everything out, but it's been very worth it. I'm another that files my circulars my date, and just clip as I need them. If I know I'm going to Kroger(20 min away) I'll go through some fliers looking for .50 and under coupons that will double that are close to expiring, and take them with me in case I can catch a deal. I only hit there about once a month though. It's helped our budget immensely, just be sure to give yourself a time to get coupons stockpiled before you get discouraged. I've saved more each month than the month before.