After buying postcards in Lisbons’ touristical shops or kiosks at Rossio Square, you need stamps (selos) to send them to your friends or family. ‘Very sorry, no stamps’ (‘Desculpa, não selos’).
UPDATE 2016: most shops sell stamps.
Rossio (square Dom Pedro V
This square is a traditional meeting point both for Lisboetas (locals) and visitors.
Besides, Rossio near Restauradores:
Portuguese like to drink a ‘Ginjinha’, a liqueur made of berries.
For stamps friendly Portuguese shopowners will explain you how to walk to a nearby postoffice.
Or they tell you to go to ‘Casa da Sorte’ (a lottery shop), where’s a little postoffice inside, Praça Dom Pedro IV, # 120.
As soon as you’re inside, you forget about the stamps….
Portuguese people love lotteries!
Queen (rainha) Dona Leonor
In the corner of the lottery shop queen (rainha) Dona Leonor, wife of the 15th century king Dom Manuel I.
She created the ‘Foundação da Misericórdia’ (Foundation for Charity) that is still very active in Portugal today. The original purpose of the Foundation was to build and manage hospitals and homes for the old and needy. Today, the Foundation has spread its wings in obtaining funds and they run all forms of Lotteries in Portugal.
Dom Pedro IV Square, or Rossio (big square), in the evening, one of the most beautiful Squares in Lisbon.
Historical information Rossio: http://en.wikipedia.org/wiki/Rossio