if(/^(((From:)|(To:)|(Reply-To:)).+)/){
print "$1\n";
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I believe if you just change your code to:

print $2 if ($text =~ /^(From|To|Reply-To):\s+(.+)/);
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That works for me in your test example.

What you should be doing is looking for the .+ part of your regex and you're not saving that bit. You need to say (.+) and look at $2 and you should be fine. I also moved the : outside your or statement as there's no need that I know of to type that : 3 times when you can get away with once. :)

Hope that helps!

There is no emoticon for what I'm feeling now.

I belive you'll find that still reads the entire file in before running the grep - so filtering the file first doesn't really give you anything.

If the size of the file is an issue you'll want to use a loop to go over it line by line. Something like this should do it:

my %name2email;
while (<DATA>) {
    next unless m/^(?:To|From|Reply-To): (\S+)\s+<?([^\s>]+)/;
    $name2email{$1} = $2;
};
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Note: the regex doesn't cope with a fair bit (multiple addresses, addresses without names, etc.).