Download?

I have just purchased this program. When I clicked "buy" it took me straight to a page where I was required to fill in paypal details and pay. Nowhere did the page ask me for my name, my email address or anything at all...

So when I paid, the thing said "thank you for your purchase" - but it doesn't lead me on to a link where I can download the program, nor does it offer me any other option of how to finally get the program I bought? I got no email (which is no wonder since it never asked for an email address). The email address I use for paypal is an email which I currently don't use - but I checked that inbox too all the same and there was no email there either.

So... paid for the thing - how do I access it?