Probably more efficient ways to do, but wanted to blow a minute or two before I went to bed.

#!perl
use strict;

my (%schds, %conts, %in_conts_not_schds);
open( MILF, "C:/junk/scheduled.txt" ) or die "Can't open scheduled.txt
+\n";
while( <MILF> ) {
  split(/\s+/,$_);
  $schds{lc(@_[0])}=1;
}
close MILF;

open( CONT, "C:/junk/contact.txt" ) or die "Can't open contact.txt\n";
while( <CONT> ) {
  split(/\s+/,$_);
  $conts{lc(@_[0])}=[@_[0], @_[1]]; #Retain case of name
}
close CONT;

foreach (keys %conts) {
  unless (exists $schds{$_}) {
    $in_conts_not_schds{$conts{$_}->[0]} = $conts{$_}->[1];
  }
}

foreach (sort keys %in_conts_not_schds) {
  print "$_ $in_conts_not_schds{$_}\n";
}

___END... FILES FOLLOW____
scheduled.txt

Sam    5:00
scott  4:45
saleem 5:00
Ken    7:00
Ken    8:00




contact.txt

sam 324-232-3333
Joe 235-309-3333
Saleem 323-747-0000
Ken 764-636-9999
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