setting up IPN (paypal)

Hi

I am a bit of a novice at this, but I am trying to install some IPN script (from http://www.web-bureau.com/modules/fr...ipn-script.php) onto my server to implement IPN.

My problem is that I am not sure how to create the following line in the database, so that the code can find the password from 'products' and 'pid':

if (strcmp ($payment_status, "Completed") == 0) {
$qry = "SELECT password FROM products WHERE pid = \"$item_number\" ";
$result = mysql_query($qry,$db);
while ($myrow = mysql_fetch_row($result)) { $passwd = $myrow[0]; }

I assume I have to create a table named products, which I have done, but where do I proceed from there? I am using phpMyAdmin which was already installed on my server.

Many thanks in advance!

Ben.