Look again in that folder for a file with a different filename but the exact same size.
BearShare identifies files by hash, so it wouldn't be fooled by a filename if the
file is actually exactly the same.

Another way to identify a file is to right-click on it in your search window and
select "Bitzi ticket". If it is bogus somebody else might have already left the
info on it at Bitzi.com to warn others against downloading it.

If you still can't figure out which one it is, move everything out of that folder
to a brand new folder somewhere BearShare isn't looking and try again. When
the download is complete you can examine the file to see what you were
trying to download.