[Sir_Dr_D]

This is where it is for me.

C:\Users\{profile name}\AppData\Local\VirtualStore\Program Files\dominions3\savedgames

If you go to one of your dominions saved games folders, such as
C:\Program Files\dominions3\savedgames\CasualPBEM
there is link in the explorer window called compatibility files. If you click on it, it will bring you to where the actual files are stored. (the first link I gave)

The easy way I hear is to not install dominions into the program files folder.