I get coupons from the Sunday paper, if it's a good week I buy more papers.
I have also in the past purchased from eBay, but not often. For some products I contact the manufacturer and request coupns, 9 time out of 10 I receive coupons in the mail from them, including for things like organic beef, etc.
Now in my family we do not eat much boxed, frozen, ready to eat stuff so sometimes it seems as if I'm not getting many coupons just because my family doesn't eat that stuff.
However, just because a coupon comes out this Sunday doesn't mean I use it now, sometimes I might hold a coupon for months before I "play" it.
I belong to a pay site that tells me when the right time to play my coupon is, when it matches up best with an in store deal.
I might not walk out with $100 of food for $3, but last week my savings was 70% and the week before that it was 78%. I love watching the cashier hit total and see the shelf amount and then apply store sales and my coupons and watch that total drop, drop, drop, and drop some more!
As for the time... maybe 20 minutes a week? I clip coupons I want each Sunday morning and have two smallish coupons holders and file them into my holders. They are both small accordian style folders, each with 13 slots. One is for food & beverages and the other one is househols (hair, teeth, lotion, pcleaning, plastics/ paper, etc).
However, since I belong to that pay site, I don't have to spend the time to match up my store ads with coupons, they tell me, so that saves a ton of time. For me it's well worth the money I spend for the service, I still am way ahead in the game of saving money.