While running Parallels Desktop, goto Window -> Virtual Machine List -> right click your virtual machine and select Show in Finder. This will usually lead to a .pvm file at ~/Documents/Parallels/
The gigantic part of a .pvm is the virtual hard disk .hdd inside the .pvm (if it's not a Boot Camp virtual hard disk). You can see the .hdd when you right click a .pvm in the Finder and select "Show Package Contents".