I saved a file in an app's application content (right clicked the application file, and then clicked Show Package Contents) for security issues. However, during the upgrade to OS X Lion, I completely forgot it was there and subsequently the app was updated and the file is gone! It was the application Stickies, in case that's helpful. Does anyone know if there's any way I can recover it?
EDIT: No longer looking for a solution, files have been found using diskdrill.
Best Answer
I managed to recover my file by downloading the free version of Disk Drill. I used the deep search options locate removed files on my Mac; you can view results by type of file, however names as far as I can see are not conserved, so you will have to preview each file one by one. To actually recover the file you must upgrade to the Pro version of the software.