Nearly everybody loses some files that they want back at some point. When that happens, you need advanced file recovery solutions. One good one is Mac Data Recovery Guru. It requires Mac OS X 10.6 or higher, costs $99 and is available here.
Mac Data Recovery Guru lets you "resurrect" deleted files with only a minimal learning curve. It can find files lost to faulty drives, even those suffering from the "click of death."
The interface lets you browse deleted files, and recover them by file type. Simply click on the lost file and it will show a preview of the contents. Click recover to save it. The only thing that can stop Data Recovery Guru is when: a) a file has been overwritten or b) secure delete has been used.
Mac Data Recovery Guru will work on drives with failing motors or the click of death. The software simultaneously provides a surface scan and a bad sector count (if appropriate). Media including flash drives, hard drives, CDs, DVDs, SSD drives and all types of memory cards is supported. If Disk Utility can see the drive, the files can probably be recovered.
The software works with all Macintosh disks (HFS filesystems, HFS+, HFSX filesystems), Windows disks (NTFS, FAT filesystems), Linux disks (Ext2, Ext3, Ext4 filesystems), Unix disks (XFS, UFS filesystems). Data Recovery Guru 2.0 will get data fragments of any kind of data and provide it in a variety of formats (such as any raw text embedded anywhere on a system, or jpegs embedded in PSDs, etc).
When you're using Mac Data Recovery Guru, it's better to allow the scan to completely finish, select the folders of the filetypes you want back (hold down the command key to select multiple folders), then hit Recover to recover entire folders of filetypes you want back, and then search through for specific files using Spotlight or the Finder. This can be quicker and easier than searching through the files using the data recovery software itself.
Data Recovery Guru works seamlessly and has a short learning curve. Like the best Mac software, it's intuitive and simple.