In general....you can often successfully recover deleted files from a PC, camera memory card or USB Memory stick, it just depends on what’s happened since the files were deleted.
When you delete files the data itself isn’t deleted, just the index entry that says where the data for those files is located. The space containing the deleted files is also now marked as free space so it is available to the system for any new files to be written there instead.
If and when that happens, then it becomes too late to recover your deleted files so it is very, very important to not save any new files or data to the device concerned.
If the deleted files are on your PC, use another PC to browse the internet for a solution as internet browsing causes lots of temporary files to get written to the disk. Download any file recovery software, for example, to a memory stick, plug that in the computer with the deleted files and run it from there.
If the deleted files are on a memory card or USB memory stick, just don’t save any new files to it.
One of the easiest ways to see if you can recover deleted files is to try some file recovery software. There are many such products available, both commercial and free – also of varying quality!
A good tip is to try the free demo version of a good commercial product that will scan the device for deleted files and show you exactly what files can be recovered.
At least that will show you if you can recover the deleted files at all or if it’s too late already.
You can find more useful information on how to get deleted files back here.