Dear Mr. Alfred:
In the page
http://www.telebrasilia.net.br/ you can find the Postal Addresses and the Telephone Numbers of the Notary's Offices of Brasília.
a) Open the page
b) Chosse: 102 Consulta à Lista
c) Write: cartorio
d) End: Procurar
The Notary's Office where the peoples married had the words "Registro Civil" or "Casamento".
The principal of the list is:
Cartório Primeiro Ofício do Registro Civil e Casamentos
SCS Q8 BL B60 S 140E
Venâncio 2.000
Brasília DF
Remember you the address of the Notary's Office where you married ?
So you send a letter to the Notary's Office where you married and ask how much is the fee and how is the payment form.
Before you to sent the letter you need know the correct ZIP number, which I can try find out and send by E mail to you.
Yours truly
Carlos Eduardo Wellichan, from São Carlos (SP), Brazil