Dan Dickerman from the IRS Criminal Investigation, Electronic Crimes Program, provided several presentations on computer forensics topics:

Advanced Data Carving

Advanced Data Carving: New Directions in Data Carving Techniques

Using VMWare in Digital Forensic Investigations

RAID Rebuilding

Unfortunately, these slides don’t include Dan’s narration, but they’re detailed enough that you can get a good understanding of each topic on your own.  Any remaining questions are a simple task for Google.