use XML::DOM;
 
 
my $xml =<<EOXML;
<?xml version="1.0" encoding="windows-1252"?>
<IDList><Details><id>Trial ID</id><name>Mooza
</name></Details><Details><id>Trial ID</id><name>bin_salim99
</name></Details><Details><id>Trial ID</id><name>dino88
</name></Details><Details><id>Trial ID</id><name>al3neeeeed
</name></Details><Details><id>TrialID</id><name>Do0oDa</name>
</Details></IDList>
EOXML
 
my $parser = new XML::DOM::Parser;
my $doc = $parser->parse($xml);
  
my $root = $doc->getDocumentElement();
 
foreach my $detail (@{$root->getChildNodes()})
{
   my $name_el = $detail->getElementsByTagName('name')->[0];
   my $name = $name_el->getFirstChild();
   if ($name->toString() =~ /Mooza/)
   {
      my $new = $doc->createTextNode('Foobar');
      $name_el->replaceChild($new, $name);
   }
   elsif ( $name->toString() =~ /Do0oDa/ )
   {
     $root->removeChild($detail);
   }
}
 
my $newdet = $doc->createElement('Details');
my $new_id = $doc->createElement('id');
my $new_id_val = $doc->createTextNode('Test ID');
$new_id->appendChild($new_id_val);
$newdet->appendChild($new_id);
my $new_name = $doc->createElement('name');
my $new_name_val = $doc->createTextNode('Yargle');
$new_name->appendChild($new_name_val);
$newdet->appendChild($new_name);
$root->appendChild($newdet);
print $doc->toString();