In the words of the great technical consultant R. Kipling:

If you can bear to hear the truth you've spoken
Twisted by knaves to make a trap for fools,
Or watch the things you gave your life to, broken,
And stoop and build 'em up with worn-out tools:
... ...

The only practical thing you can do is to recommend that she get started immediately on rewriting the document - while it's still fresh in her mind. Since she's had a "dress rehearsal" it should go much more quickly the second time around - if she gets onto it before it goes stale. (She should be getting started even if there might be some hope of a recovery - which there probably isn't in this case. If you really think something might be recovered, of course she should use a different computer.)

You've checked the places where there might be a copy of some or all of the file she wants, and it's not there. The places checked are all the reasonable ones, with the possible exception of a backup file made by Word, if the program was set up to make one. In Word 2007, autorecover files can be set to be in a different folder than the working documents, but the last save should have deleted any autorecover files on completion of the save. Rarely, Word will leave one after a save, but it's a "malfunction" if it does. [In Word 2007, Cowsplat|Word Options, at "Save" will show where they should be, just in case you want to look.]

If this was a critical piece of evidence meriting forensic methods, a modern version of one of the old-fashioned file recovery programs that lets you "restore" deleted clusters might be able to find some bits and pieces; but it would take you a lot more effort to put the pieces together than for her to recreate the original, even if you had a program that could do it. Since the files probably are binary (depending on Word version) and you probably won't recover the head/tail segments of the original file (they were used for the last save and are now part of the crumpled file), getting the bits back into anything that can read them is an advanced procedure.

If you don't already have such a program installed (which I'm fairly certain you don't) installing one on the affected drive would likely wipe out much of what might be there.

The old programs that you used to be able to run from a floppy disk can't handle the hard drive sizes common on current kinds of computers, so far as I've seen. Newer programs need to be installed before the problem occurs, or must be installed on a separate hard drive from the one where the problem is located. And they're seldom successful, except in the hands of someone with lots of criminal experience. (You may qualify on the "criminal" part; but it really needs to be a specific kind of experience as well.)

For future reference, a friendly discussion on the handling of incidents where "Sh*t Happens" might help the victim. Some discussion of the use of Ctl-Z (Edit|Undo) and advising her to "Save As with a different filename" when there's an unexpected happening might be some consolation and some help in the future. Her response was probably a "natural" one; but some friendly words about better ways to respond to the occasional oops may be helpful, and avoid her fearing that it's going to happen again right away.

John