Just split on each line with spaces-surrounded | as separator. You'll get a list with two elements, the first (element 0) is the IP and the second (element 1) is the text. You can store them in a hash to access it later.

my $entries;
while (<DATA>) {
 chomp;
 my($ip, $text) = split /\s+\|\s+/;
 $entries{$ip} = $text;
}

print $entries{"192.168.0.1"}; # some text

__DATA__
192.168.0.1 | some text
192.168.0.2 | another text
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Update: Anno makes it better for anticipating unexpected input. I did solely by the fact of the sample input. I know about \s* and limit in split.