Making A Map

I like to make maps for Civilization and don't think I'm averse to actually doing something on the map maker of course, but I was just wondering if I was making a map (e.g. a US map) is there any fast way to make sure the land is accurate rather than hand-plopping down every tile? Not that I'd shy away from it, of course, I was just wondering if there's a quicker way to make more accurate maps.