You can access your desired information several ways using XPath. For example: 
/Parameter/Value/Item
/Parameter/Value/Item[@Value]
//Item

[download]
These all can get you to the node you desire.
I assume from your Xpath that this is a snippet of the acutal XML file your are parsing. If you want just one of these values, you would want something like the XPath you mention in your post. But if you wanted all the Values in your XML, use the 3rd one I listed.
Check out W3 Schools XPath for more information on XPath.

One of the reasons I prefer XML::LibXML is the XPath support
Try 
use XML::LibXML;

#Parse XML
my $template = 'xmldocument.xml';
my $parser = XML::LibXML->new();
my $doc = $parser->parse_file($template);

#Find desired node(s)
my @nodes= $doc->findnodes("//Item");

#Print results
for(@nodes)
{  if($_->hasAttribute("Value")
   {  my $data = $_->getAttributes("Value");
      print "$data\n";
   }
}

[download]
Update:Fixed typo

In reply to Re: XPATH and perl by ramrod
in thread XPATH and perl by yorozen

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.