Make sure you enable Shipping/Buyer's Address in the settings of each product that should trigger collection of a street address during checkout. If no items in an order have that setting enabled, no address would be collected, so the address variables you mentioned would not be transmitted back to your URL.
For actual PayPal payments, we simply forward the entire, original PayPal IPN we received (along with our extra, non-IPN variables) to your URL, so you will probably see some PayPal-specific IPN variables that we don't document. However, the variables we do document would be sent (if applicable to the order) to your URL for all orders even if PayPal was not involved in checkout. PayPal documents their own IPN variables here:
https://cms.paypal.com/us/cgi-bin/?&cmd=render-content&content_ID=developer/e_howto_html_IPNandPDTVariables