Either pres 'Ctrl + Z' or go to 'Edit' in the browser window and select 'Undo' to undo the folder or file move. For future reference, when you accidently move a file you can do one of two things to correct this (if done immediately after the move).

Click on 'Browse' on toolbar in upper left hand corner.It's a very simple program and has been scanned by ( click here for results) to be malware free. This program will scan any directory chosen by the user and show the most recently modified or created files for that directory. There are a couple of ways to gather this information but for this case I would recommend ' Last Changed Files' from. Firstly, unless I missed a custom log, there is nothing in Windows 7 'Event Viewer' that will show folder or file relocation activity.