+1 on the local dealer. I looked at tires for about 2 months, internet pricing, Wally World, and even the big chain speciality stores. The local guy gave me the best price as well as the best customer service. Try to stay local if you can. After about 2-3 sets as a repeat customer, then you'll really see some discounts come your way.

PS - Truck tires ain't real cheap anywhere! Just found that out personally.