If you're talking about the local steet maps, then any service station, convenience store, or supermarket will have them.

If you're looking for a state atlas or the big Thomas Guides books, I'd check the local bookstores.

Of course any map-specific store will have them, or you can order them directly from Rand-McNally or online.
_________________________
Hope for the best and prepare for the worst.

The object in life is not to be on the side of the majority, but to escape finding oneself in the ranks of the insane