An example of php looking up book information on the amazon website based on the isbn isbn

Plug-in description:
The plug-in looks for the book's details on the Amazon website based on the 10-digit ISBN isbn number provided.
If the result is found, a two-element array is returned, where the first element is the title of the book and the second element is the URL address of the abbreviation diagram for the book's cover.
It requires the following parameters: $ISBN 10-digit ISBN isbn

$isbn   = '007149216X';
$result = PIPHP_GetBookFromISBN($isbn);
if (!$result) echo "Could not find title for ISBN '$isbn'.";
else echo "<img src='$result[1]' align='left'><b>$result[0]";
function PIPHP_GetBookFromISBN($isbn)
{
   // Plug-in 93: Get Book From ISBN
   //
   // This plug-in looks up an ISBN-10 at Amazon.com and then
   // returns the matching book title and a thumbnail image
   // of the front cover. It requires this argument:
   //
   //    $isbn: The ISBN to look up
   //
   // Updated from the function in the book to take into
   // account changes to the Amazon HTML.
   $find = '<meta name="description" content="Amazon:';
   $url  = "http://www.amazon.com/gp/aw/d.html?a=$isbn";
   $img  = 'http://ecx.images-amazon.com/images/I';
   $page = @file_get_contents($url);
   if (!strlen($page)) return array(FALSE);
   $ptr1 = strpos($page, $find) + strlen($find);
   if (!$ptr1) return array(FALSE);
   $ptr2  = strpos($page, '" />', $ptr1);
   $title = substr($page, $ptr1, $ptr2 - $ptr1);
   $find = $img;
   $ptr1  = strpos($page, $find) + strlen($find);
   $ptr2  = strpos($page, '"', $ptr1);
   $image = substr($page, $ptr1, $ptr2 - $ptr1);
   return array($title, $img . $image);
}