Travelling around Brazil for 3 months - advices? (São Paulo)

Bom dia/tarde!
My name is Francesca and I will be travelling around Brazil for other 3 months (Dec-Jan-Feb) to complete a book / travel guide for an italian editor.

I have just finished a phd in Economic Geography and I work in Tourism & Communications since 8 years ago.

Any suggestions, advices or contacts that will make my life easier in Brazil are welcome!

In December I will be around: Foz de Iguazu, Curitiba, Florianopolis, Porto Alegre
Christmas/New Years Eve: Salvador
January: North East until Natal (including Fernando do Noronha)
February: Rio (and hopefully Cuiabà) before finishing in SP.

Thank you for your time and consideration!
Francesca