NTFS partition: recovering deleted files

[James Collier]

Hi everyone,
I had a bit of a panic today.
A friend of mine whom, unfortunately, doesn't use FOSS yet (Windows),
has accidentally deleted a lot of important business MYOB accounting
files.
He's started a program to recover them called "PandoraRecovery".
Sorry this is slightly off topic but I thought this would be a good
place to ask given the enormous amount of general computer experience
most of you have.
My question is: what, if anything, could be done to help him?
Thanks,

James C