It usually pays to buy your local Sunday morning paper, because of the coupons and supermarket circulars.  These two resources will more than make up for the $1-3 you spent on the paper.

Some helpful tips:

1. Only use coupons on items you really use
2. Try to combine the coupons with in-store sales for bigger savings
3. Shop at stores that double or triple coupon values
4. If the coupon doesn't limit you to just one item, buy multiples

I love getting my receipt and seeing 30-40% savings (I have seen 50%+ on occasion) due to coupons and in-store specials.

I also look for coupons in the free local cultural tabloids that I have seen all over the country.