Hello all, im new to using paypal on a website and also this forum.....hi!

I have a series of buy it now products for sale on my site and it all works nicely.
After a customer has purchased an item, they are directed to a html form to fill in some more details and this is then passed to a pdf and a database. What I need to do is to pass some of the details from the buy it now transaction on to my html form on the following page so it can then be used to form part of the pdf and database. Is this possible? Most importantly is the PayPal reference number but some other things might be nice too.
I get the impression that it is possible but cannot figure out how to actually do it.

thanks