$filepath = "C:\\Perl scripts\\test";

# $GetName is a filename that they want to use as a template
# to change all the filename that are similar within a 
# directory(user input, they will add the parentheses also). 
# The parentheses () are used for a parameter
# they want to keep for adding to the final file name
$GetName = "test_0(02.txt)";

# $StartCh is the 1st number they want to start with, so
# for this example 
$StartCh = 1;
$EndtCh = 12;

# $SetName is the final filename so for example
# the 1st file lets say is test_001.txt.
# Based on the $GetName and the SetName the final filename
# should be changed to "Chapter 01.txt". 
$SetName = "Chapter \1";

opendir (DIR, $filepath) || die("Cannot open directory");
while ($file = readdir DIR) {		
	print "$file\n";
	# Matches for anything before parentheses
	if ($GetName  =~ m/(.*?)\(/) {
		$subname = $1;
		if ($file =~ /^$subname/) {
			for ($i = $StartCh; $i <= $EndtCh ; $i++) {

				# This reg ex could possible match alot more than I want.
				# It would give me the wrong result, for example
				# if the filename is "test_005_1.txt", it would pick
				# it up even though thats not what I want
				if ($file =~ /$i/) {
					# This is where I am going to have problems
					# especially if they do something like this
					# $GetName = "test_(02-092010.doc)" the
					# number of digits would be totally off
					my(@origdig) = ($GetName =~ m/\d/g);
					my $orig_cnt = scalar(@origdig);

					if ($StartCh => 1 and $EndtCh =< 9 and $orig_cnt=1) {
						$num1 = $origdig[0];
						$replace = $subname . $i; 
					}
					if ($StartCh => 1 and $EndtCh =< 9 and $orig_cnt=2) {
						$num1 = "0" . $origdig[0];
						$replace = $subname . $i;
					}
					# In case they may include the extra 0 
					# example $GetName = "test_(002.txt)".
					if ($StartCh => 1 and $EndtCh =< 9 and $orig_cnt=3) {
						$num1 = "00" . $origdig[0];
						$replace = $subname . $i; 
					}
					# More If stmts to do the same for >= 10
					# How would I go about writing this to be more 
					# efficient and be cleaner?
				}
			}			
		} 
		else {
			print "$file does not match\n";
		}
	}
	else {
		print "GetName didnt have parentheses\n";
	}
}
closedir DIR;

Example of file names in the directory  in this case:
test_001.txt
test_002.txt
...
...
test_012.txt