This is a little place where you don´t need to spend much time, unless you really want to relax or have a romantic time with someone. Most people visit Trindade, while staying in Paraty, since Trindade is very close to it.
And there is even a better option, that is to visit also Ilha Grande, and spend about a week or more there, since you´ll have a lot to see, then spend some days at Paraty, and during those days go to Trindade. But if you wish to stay in Trindade, there you´ll find campings and Inns too.
Those places are full of travellers from all the world, I went to Ilha Grande two weeks ago, and I can surely say that there were more foreigners than brazilians visiting the Island.
Here a list with some of Trindade´s beaches:
Praia do Cepilho
Praia do Rancho
Praia do Meio
Praia do Cachadaço
Praia das Figueiras (exclusive for naturists)
This is it, if you are looking for a good place to do some trekking, or just relax, Trindade is the place for you. And bring your surfboard and your diving equipment, since here you´ll have good spots for both sports.