The North-West part of Brazilis known as "kite-heaven": During the season from July to January, daily wind is almost guaranteed at the right spots! In the region around Fortaleza, it's usually 15 to 30 knots - further north it get's stronger (up to 40 knots!), further south it get's lighter.
There are countless great spots in northeastern Brazil. Most kitesurfers arrive in Fortaleza and stay a few nights in nearby Cumbuco. There you can rent a car and start your discovery.