title: Send email after PayPal Purchase
body: <p>I have a form on Booking process page of my website. Below that form I have a PayPal button that leads to PayPal payment page. I'm passing few values like: price, name of tour and currency to PayPal regardless of that form that I've mentioned.</p>
  
  <p>That form above PayPal button needs to be filled in and then user should click on PayPal button. After that he needs to make a payment on PayPal. That's working!</p>
  
  <p>Now, I need, when the payment is over, from PayPal to send back variables from that form on some page of my website from which I could send PHP email containing those values.</p>
  
  <p>How can I accomplish this?</p>