I am new within this feild, all things i want is really a custom wordpress widget to complete ajax call which will call my asp.internet page which in turns display an html table of items.

Can someone assist me to with this particular please?

Suggestion, presuming this needs to be achieved with ajax and may 't be completed with plain php throughout the page load:

Make ajax request to some php script on a single domain. That php script interns loads the exterior HTML via php's curl implementation, or whatever other exterior scraping type techniques can be found.

For that ajax itself, use jQuery (bundled up with Wordpress), simple pseudo code:

 <?php wp_enqueue_script('jquery'); ?>
 <script> 
 jQuery.get('/some/path/asp.php?some=args&go=here', function(data) {
      jQuery('my_div').html( data );
 }); 
 </script>


 <?php  
/**
 * @file asp.php
 */
  echo ( $html = file_get_contents('http://remotehost.com/products.asp?$args')) $html: 'no way jose';