use MP3::Info;

opendir(DIR, ".") or die "can't opendir $some_dir: $!";
@files = grep { /mp3/ } readdir(DIR);
closedir DIR;

for (@files)
{
  my $tag = get_mp3tag($_) or 
    print "Could not access tag on $_\n" and next;

  my $newname = $tag->{"ARTIST"} . " - " . $tag->{"TITLE"} . ".mp3";
  `move "$_" "$newname"`;
}