When files are deleted they still remain on camcorder hard drive and can
be recovered, unless they have been overwritten by fresh data. The only thing to do so run a data recovery program
to see what can be recovered. The only program I have tested is
asoftech data recovery software and it had done the job well. download
the data recovery from http://www.asoftech.com/adr/Select the drive where your files were deleted and then do a deep scan. It will find your deleted files.
Those deleted videos are highly possible to be recovered, you should use video recovery software to help, here are some programs you may rely on. Both programs can also recover photo and music files.
A Tip:Before your videos are recovered, do not attempt to save more files to the handycam memory card or stick in case the original files(your videos) are overwritten.