try this one
www.correos.es/codigopo/streetanswer.asp?street=tarragona&city=MADRID&x=19&y=5 what i did is i put in the name "madrid" and clicked on "ver el codigo". then it lists many names and zip codes, scroll down to where it gives you an option where it says "Pulse aquí para introducir el nombre de la calle" and you click there and put in the name of the street, don't enter c/tarragona, just enter tarragona.
[This message has been edited by missmadrid98 (edited 11-16-2000).]