[femto]

Chances are that most of the information is still physically there, just that it is inaccessible. First thing I would do is physically obtain the drive, so even if it's inaccessible you have the information in your possession.

From your blog post, I'd assume you don't have the knowledge to attempt recovery yourself, so call in an expert to handle the data recovery for you. At this stage, it is a matter of what the information is worth to you, compared to the cost of recovery. Almost any intervention is possible, for a price.