I will get you started. This gets you the time string. Convert that to epoch. Convert current time to epoch. Then compare within 30min*60secs_per_minute = +- 1800 seconds. 
#!/usr/bin/perl -w
use strict;

while (<DATA>)
{
   chomp;
   my ($time, $type) = split(/:>/,$_);
   if ($type =~ m/\s*FIND/)
   {
      print "I need to something with: $time\n";
   }
}

#PRINTS:
#I need to something with: 7/21/2009 5:49:20 PM
#I need to something with: 7/21/2009 5:52:59 PM

__DATA__
7/21/2009 5:47:29 PM:> DATA
7/21/2009 5:48:49 PM:> DATA1
7/21/2009 5:49:20 PM:> FIND
7/21/2009 5:50:39 PM:> DATA3
7/21/2009 5:51:29 PM:> DATA4
7/21/2009 5:52:59 PM:> FIND
7/21/2009 5:53:19 PM:> DATA6

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In reply to Re: Find the text by Marshall
in thread Find the text by Selvakumar

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