Generally speaking, when you write a Ghost image to a drive, it starts laying the data down at the start of the disk and continues consecutively over the disk until the end of the image is reached.
You problem is that any data in the first part of the drive that has been overwritten by this image is now toast - i.e. it can no longer be recovered. However, if there is any of the old data left on the drive after the image stopped, then this is still recoverable.
You need to download Recover My Files from
www.recovermyfiles.com and run a Complete File Search of the drive letter. This search will only look in the "empty" part of the disk. It probably will not be possible to recover the original file names, as this information is held in a table at the start of the disk and has most probably been overwritten and destroyed.
So in the results window, click on each file found to preview its content, and with any luck you will find at least some of the files that are important to you.
Good Luck.