I made a map in Google SketchUp. Rather than one superstore, I've split it into a supplies store and a food store, so that players will have to be even more active than before. I tried to keep it diverse. Let me know what you think.

[url]http://fav.me/dbu183p[/url]

[i]Legend[/i]
White: Start Location
Lines: paved roads
Dark Gray: blacktop (parking lots)
Dark Green: trees. Two of them are mistakenly shown as gray circles, sorry about that.
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G: Gear/Supplies store
F: Food/Water store
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Tan: farm field
Brown: farmhouse
Purple: two-story townhouses
Red: one-story brick houses and brick paths
Purple: radio tower
Light Green: military base/checkpoint
Yellow: power plant and power lines
Blue: apartment complex