Creating a receipt on the fly

I have created a simple ordering form on my site where I use Checkout-service to make the direct-payment possible. This works fine but now I’d need to create a receipt for the customer automatically when customer returns to my page after a succesful payment. How could I do this; there would be certain static-texts on the receipt and of course the person’s name and the payment amount needs to vary according to the order. Best solution would be if I could create a pdf-file to be sent via email. Any ideas how to implement this?