use File::Find;

sub wanted {
   return unless -d $_;
   push(@File::Find::matches, $File::Find::name);
}

sub find_it {
   local *File::Find::matches;
   find(@_);
   return @File::Find::matches;
}

{
   # Not a global.
   my @dirlist = find_it(\&wanted, shift(@ARGV));

   # Use @dirlist here
}