I've used google earth for a lot of things including modeling wind farms with 3D turbines. Sketchup is a good add on and has a ton of 3D models ready to use. I didn't have to make my own turbines. I wish they would add more mapping utilities for overlaying things like townships, section lines, etc. A lot of that kind of data is available from the State governments but I have have a for-pay program called Global Mapper to make good use of it.
I have no complaints. Google earth has a lot to offer map makers and it's free.