depends on how you deleted it.
Maybe you'll get lucky and they'll still be in the recycle bin.
And there are programs that can sometimes save deleted files. You may want to
investigate them--on a different pc. (You don't want to overwrite any "deleted"
space before you get a chance to recover it.)
I think Norton utilities has a feature like that. It's called UnErase, but I
don't own it and I'm not sure it's still available.
If you can't find them, maybe you've emailed them to someone else--check your
sentbox or even the recipients.
David McRitchie has some notes about backups at:
http://www.mvps.org/dmcritchie/excel/backup.htm
They might be helpful for next time(????).