Thank you for your suggestions. I have incorporated a number of them into my program, as well as made it more streamlined. However, my problem still remains. I need to print the data from @signal into consecutive columns, as shown in my post at the end of the thread. The only way I know how to make this managable is to take the data pushed into @signal, grep it, and then shove it into 5 separate arrays (there are 5 input files CURRENTLY). This is all well and good, except that I need to somehow make this program capable of handling different numbers of files each time it is run. Do I need to manually assign, say 30, arrays in which to put the data, placing a limit on the program? I'm sure there are better ways to do this, but I don't know how.
NOTE: please be patient with me, as I'm only a beginning programmer, perl being my first language. Having only been working with it for a month now, I suppose I could be doing worse...:-)
My latest code:

#! usr/local/bin/perl -w

use Cwd; 
use IO::Dir;
use IO::File;

print STDOUT "Please enter the name and location of the directory to p
+arse\:\n";

chomp (my $directory=<STDIN>);

open (OUTPUTFILE,">junk.txt"); 

my $dh = IO::Dir->new($directory) || die "Cannot open directory '$dire
+ctory': $!\n"; 

my @filenames; 
push @filenames, $_ for map { "$directory/$_" } grep !/^\.\.?/, $dh->r
+ead; 

$dh->close;

@output=get_signal;
for (@output){
@{$signal[0-4]};
@{$rprobe};}

print OUTPUTFILE "@signal";
close OUTPUTFILE;
exit;

sub get_signal {
   while (@filename) {
       $file=shift @filename;
      use Cwd 'chdir';
      chdir "./data";
      open (FILE, "$file") or die;
       @data=<FILE>;
       my $i=0;
      foreach (@data) {
         next while $i++ <=14;
         push @signal, (split(/\t/))[3];}
      my $g=0;
      foreach (@data) {
         next while $g++ <=14;
         @probe=(split(/\t/))[0];}
      $hash{$file}=\@signal;
      close (FILE);
   }
   @values=values(%hash);
   $rprobe=\@probe;
   return @values;
   return $rprobe;
}
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