Nubwagon,
The most common cause of a dog constantly licking it's paws is allergies. Often it is something in your yard or where the dog hangs out. This can be from a minor annoyance to the dog licking it's paws bloody. The paws are itching and they lick them in attempts to stop the itch.
If you do an internet search you can read about it and different things to try to alleviate the allergy.
An easy way to start is to wash the dogs paws off when ever it goes outside and then comes in the house. Another thing that I have had work is soaking the dogs paws in a mixture of providone iodine. This can be found at any pharmacy and is inexpensive. Mix some in a small bowl of water till you get the color of a strong tea. One at a time soak the dogs paws in the mixture for several minute each and then let it dry by itself. If the licking continues or seems to severe you can bring the dog to the vet. Many have had good response from an allergy shot.
Hope this helps,
Joe