I will need to do a 3D representation of a terrain and I heard surfer is ideal, but then I do not have a DEM file of the region, I know Google Earth and Map could help, but I do not know how? If there is another way round, please where can I get one for free?
You can use TCX converter for generating DEM from google earth. Check this Contours and DEM from Google Earth
You can use ArcGIS with ArcGoogle tool to download DEM from Google Earth and create contours from DEM
Here's clip for you: https://www.youtube.com/watch?v=OKZ4gJokg7o