The following might get you started. Cheers. 
use strict;
use warnings;

while (my $line = <DATA>) {
    if ($line =~ /^id:\d+/) {
        for (1 .. 4) {
            my $following = <DATA>;
            print $following;
        }
    }
}

[download]
__END__
John, Doe Michael
id:1234567890123 library:ACME
City, state:PUEBLO, CO
Phone:719-555-555
Street:1610 Sorrow AVE APT D
Zip: 81004

Shakespeare, William
id:4567890123999 library:Fisher Fine Arts Library
City, state:Philadelphia, PA
Phone:215-898-8325
Street:Locust
Zip: 19104

[download]
prints: 
City, state:PUEBLO, CO
Phone:719-555-555
Street:1610 Sorrow AVE APT D
Zip: 81004
City, state:Philadelphia, PA
Phone:215-898-8325
Street:Locust
Zip: 19104

[download]

Update: Sorry, jbert, your post was not on yet when I started.

In reply to Re: Print 4 Lines below matching criteria by fenLisesi
in thread Print 4 Lines below matching criteria by Anonymous Monk

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