I never exchange tanks and have never had the slightest problem finding somewhere close to get them filled. Even Costco is getting into the act. Call your local hardware store (Ace ?) and ask if they do refills if you're having trouble finding a place.
I still remember standing in a long line at the propane refill station at an Ace near Orlando prior to a hurricane alert (Charlie I think). Everyone refills their propane grill tanks just in case the grill becomes the post-hurricane go-to household stove for a while. Which it did !
