I'm new to this process, so this is a simple question.
I put my ARW Sony A7S2 files into a folder on my desktop. 
However, this folder doesn't show up in the listing on the left side of the LRTimelapse window. 
What am I doing wrong? Why am I not able to import these files?
Thanks,
Eddie

LRTimelapse shows any folder. But if you are used to find the Desktop at top level, you might not - because that are only shortcuts that Explorer and Finder show there. So go to Users / Your username / Desktop there you will find you folders.
The same goes for external drives, on mac you will find them under "Volumes" in LRTimelapse.

I have the same problem , i can not find the volume of the sdcard

It would help us to help you, if you could tell us if you are on mac or pc. Can you see the SD card in the explorer or finder?
If you inserted the SD card after you started LRT, you should refresh the folder view with the little blue arrows on the top right of the folder chooser in order to rescan and find the SD card.