Editing file info

[slickassnot]

Hello all,

I just downloaded a collection of some 500 mp3's. They were named 001 through 500+[filename]. Getting rid of the indexes was easy enough (I like it 'clean - just the filenames, ma'm) using a (paid-for (!) utility called File renamer.
However, all files have unwanted entries in the File Info box; there is a Title entry consisting of an index corresponding to the filename index. Also, in the Artists entry, they all have, for some reason, 'Various Artists' which obviously shows up in Winamps main window.
Now for my question: is there a way to get rid of these unwanted entries in the File Info en masse, so to speak, in one fell swoop, or do I have to (perish the thought!) do it file by file?