The prime kite-surf and windsurf spot in Florianópolis is the Lagoa da Conceição. Experienced surfers can rent gear from Open Winds.
Prices for renting gear start at R$45 per hour.
Beginner kite surfers can take a course at Open Winds. 90-minute lesson cost around R$200. You will need a minimum of 4 lessons to get absolute basics.
Another windsurfing a kitesurfing school and store on the island is Windcenter.