Either from your remote website (if the something has been published) or
from your backups. When FrontPage deletes anything, it is deleted
permanently.
There is a very remote chance the file may exist (with an obscure name)
in the FrontPage temporary files. These are at (in Windows XP):
%USERPROFILE%\Local Settings\Temporary Internet Files\FrontPageTempDir
Type or copy/paste this into the address bar in Windows explorer.