I've had a few people ask me where I go to get my coupons. First, the best place is your newspaper. If you find some good coupons in it, go back later in the week and get some more copies for even cheaper!
I also made a list of links on the left hand side of my blog to online printable coupons that I have found. Some are local but you can probably find something similar in your area... just google! My favorite link is Coupons.com and the coupons at Target. They seem to have the most useful ones for me. Most of these sites also have links to different kinds of coupons like groceries, retail, restaurants, etc.
If you know of any others, please share! Thanks! :)