Read in xml file

I want to setup a javascript page on my website where I have a xml file that has a name comment and gps coordinates. The user types in the name and and it searches the xml file and spits out the comment and coordinates.  My main question is where can I upload file for my page to search and how( what path do I use to read it in)

So my code is in a embedded code block, and there is no link editor, so how do upload the file?

So this is my code if I use the path  "/s/cd_catalog.xml" or  "cd_catalog.xml" I get a status of 404

If I use  "s/cd_catalog.xml" I get a status of 0 which doesn't make sense

<button type="button" onclick="loadXMLDoc()">Get my CD collection</button>
<br><br>
<table id="demo"></table>

<script>
function loadXMLDoc() 
{
  var xmlhttp = new XMLHttpRequest();
  xmlhttp.onreadystatechange = function()
  {
  var table=this.status;
  document.getElementById("demo").innerHTML = table;
  };
  xmlhttp.open("GET", "s/cd_catalog.xml", true);
  xmlhttp.send();
}

</script>