There are a couple of coupon printers on the 'net; if you haven't used a required one before you'll be prompted to add it to your browser. I've never had a problem with coupon printers, but always check the source. These coupon printers are a service which keep you from abusing the coupon, but if you hit your browser's "back" button you can usually get two copies.
For maximum value, watch for sales to stack with your coupons. Most coupons printed online are good for a month, so you don't have to run right out and redeem them. E-coupons are not usually allowed to stack with identical paper coupons, but present your paper ones anyway; their system will kick it back if it's a duplicate of an e-coupon.
Better Oats Oatmeal: When hubby got the word that his cholesterol was getting high we started eating oatmeal. We tried a lot of varieties and fell in love with Better Oats Oat Revolution, which are just the tastiest instant oatmeal varieties we've tried. Their Facebook page has been having regular BOGO and buy-two-get-one coupons. You'll have to "Like" it first. The BOGO coupons bring our cost per serving to 14¢.
Ronzoni: Mmm, pasta! Ronzoni has the nicest whole wheat pasta I've tried as well as a couple of other healthy varieties. Their website has had coupons monthly for three different Ronzoni varieties. You have to sign up but you can skip the newsletter. With sales I've been getting this high-quality pasta for $1.50 a box, which here is an awesome price for premium pasta.
Campbell's: They do more than just soup! Hit their website for coupons on V-8, Pepperidge Farm, Prego, and Pace. Oh, soup too!
Proctor and Gamble: If you use Proctor and Gamble products you absolutely must hit their website. You can print coupons or pre-load them onto your supermarket club cards. Note that the P&G Saver and the P&G Sampler are separate programs, check them both out. Their brands include Crest, Nice & Easy, Tide, Downy, Puffs, Cover Girl, Swifter, Always, Tampax... just lots of quality brands.
Grocery Store Sites: Your favorite grocery stores may now allow you to pre-load coupons onto your membership card. I use Fred Meyer and Safeway.
MyPoints: I've been a MyPoints member since it was Bonus Mail (yes, if you click that link and sign up I get points). They now work with Coupons.com and Smartsource.com for printable coupons, and using these coupons earns you more points. You could go directly to those two coupon sites, too; they tend to have different offers.
Shortcuts.com: This site lets you print paper coupons and also load them on your store club cards.