If you aren't using Google Maps to procure maps for your games then let me tell you a secret... Google Maps is the Best Mapping Resource You Aren't Using. Regardless of the genre of game you are playing there are maps out there got you.
Here is an example.
I got this map from Google Maps Terrain View, and though I made a few changes it remains basically the same. Do you know where this is? Most probably don't...
However, if you enjoy the works of H.P. Lovecraft you know the area, it's Essex County, part of an area known as Lovecraft Country. I am working on this map for the Sons of Ipswich game I'm working on.
You don't need to be playing a Call of Cthulhu game, or really any game that takes place on earth, to take advantage of real world maps. Had I labeled the above map with a series of fantasy names and said it was the Barony of Kravoria how many would have known it was actually a real world location? If my group was from Essex Country obviously they would, but if that were the case I could just use a map from Germany, New Zealand or any location which your players are unfamiliar with.
The level of detail in terms of things like topography and climate is extremely high and is there for the taking. Why not take advantage?
|A map of part of Southern New Zealand...|
|...or a Fantasy Realm?|