Disappearing Excel Files

I am using Vista, with Office 2007 Home.
>
> Over the last week, I have had 2 excel files disappear. I know I didn't
> delete them, they both had important data. Unfortunately backups are old - I would really like to recover the files!

I have not recently created the files, they have both been created about a
year ago, and were regularly used and updated. There has never been a problem
with the files before.
>
> They show up in the recent items list, but as an orphan link (says the file
> has been moved or deleted) in both recent documents and excel.
>
> They are not in the recycle bin, or found in any searches even by date and I
> have done a variety of searches from the explorer and the command prompt and
> they are nowhere to be found.
>
> Other people on the net appear to have had this problem with Excel files,
> but there does not seem to be a solution to recover them.
>
> Can anyone help ? Thank you !