Here's a great printable to match with a sale:
Buy Two Get One Free Starkist Solid White Tuna Cans Printable Coupon
Thanks, Couponing For 4!
Note: This is hosted on Sav-a-Lot's site but it's a manufacturer's coupon that you can use anywhere. (Some of the other ones on the link are exclusively for Sav-a-Lot, though. There's a little symbol by the exclusives.)