Hi,
I'm a retired helicopter pilot and would like you to check the ABRAPHE (Brazilian Helicopter Pilots' Association) link:
ABRAPHE - Associação Brasileira de Pilotos De Helicóptero
As said above, the radio comms are in portuguese language, but all the major and intl airports have english spoken controllers.
For you to fly in Brazil with a brazilian regitration aircraft, you must get the Resident Permit and the brazilian ICAO license or a temporary permition if a non-brazilian registration aircraft is available.
The "N" registrations flying in Brazil are temporary converting to brazilian registration awaiting paperwork or leaving the country in some months.
The Helicopter market was really heatting up till this world financial crisis hit... Only AGUSTA sales for 2009 were reaching 100 helos, but now nothing is cretain anymore.
Good luck.