I have tried everything to get mods on Euro Truck Simulator 2 but it says I need a base file. I have looked everywhere but can't find it. Do I have to download it or should it already be there on the system when I downloaded the game onto my computer?
It should be in C:\Program Files (x86)\Euro Truck Simulator 2\base.scs (when you have default installation folder in Windows 7). Maybe you have hidden that file. Here is nice tutorial showing where is the file: