I always check O'Reilly's first. The one I shop at has a couple ASE certified parts guys. Good part about that is that they know what that big pile of books are for. They also like to teach the newbies about them. There is one guy that actually likes to see me walk in. He says I give him a challenge. He owns a pretty sweet old Chevelle. After he saw how mine runs (I gave him a ride to lunch one day), he is shopping for a superduty.