For some reason, not all areas get the Sunday Coupon Inserts as part of their Sunday paper. Evidently, there are different contracts each paper has with the insert providers, so your paper may only carry inserts from one or two or none of the three insert providers (SmartSource, Redplum, and Proctor & Gamble). Not to worry, if you are one of the unlucky ones, there are other ways to get your inserts.
By Mail: In some areas these inserts are mailed out to your home instead of included in the Sunday paper. Personally, I think this is a nice perk as it would save you a bit of money. If you have a PO Box it's even better because you can often find extra copies that have been left behind by other box holders who don't want them.
If the inserts are not included in your Sunday paper and are not delivered to you automatically, you can sign up to have them delivered at the provider's websites. To see if Redplum is included in your local newspaper and where to find it, click here. You can also sign up to receive the RedPlum Mail Package here.
If your area does deliver the inserts via regular mail, you may want to stop by the post office the day after they are delivered to see if they have any extras. You can also check around the PO box area for those left behind by others.
By a Different Paper: If you live near a larger city, you may want to pick up that paper instead of your local paper, as it's more likely to have more inserts.
Extra Sources: Some areas may have other local freebie papers that include copies of certain inserts. For instance, in my area there is a small paper geared towards military and government contractors, called "The Redstone Rocket" which usually includes the weekly SmartSource insert.
Ask Friends & Neighbors: If your area does include the coupon inserts but you don't want to pay for the paper, ask your friends and neighbors if you can have their inserts. Most of them probably don't use them and would be happy to save them for you, rather than throwing them away.