For the risotto: Melt the butter in a large saucepan over medium heat. Add the shallot and cook until they are softened, about 3 minutes. Add the garlic and cook until fragrant, 1 minute. Add the rice and stir with a wooden spoon to combine the onion mixture with the rice. Add the wine and simmer until the liquid is evaporated. Add 1/2 cup of the stock and stir until almost completely absorbed, about 2 minutes. Continue adding the stock, 1/2 cup at a time, stirring constantly and allowing each addition of stock to absorb before adding the next. You may need to add an additional cup of water. Cook until the rice is tender but still firm, about 20 minutes. Remove from the heat. Stir in the Parmesan, lemon juice, parsley, salt and pepper. Spray a baking sheet with the nonstick cooking spray and spread the risotto out on the sheet to cool to room temperature, about 15 minutes.
For the arancini: In a large bowl combine the risotto, 1/2 cup of the panko, the Parmesan and the eggs. With damp hands, use about 2 tablespoons of the risotto mixture to form 1 3/4-inch diameter balls. Make an indentation in the center of each ball and insert a cube of lobster. Cover up the hole to completely enclose the lobster and roll the balls in the remaining 1 1/2 cups panko to coat.
In a large, heavy-bottomed saucepan, pour in enough oil to so that it is 3-inches deep. Heat over medium heat until a deep-frying thermometer inserted in the oil reaches 350 degrees F. (If you don't have a thermometer, a cube of bread will brown in about 2 minutes.) In batches, fry the rice balls, turning occasionally, until golden, about 4 to 5 minutes. Drain on paper towels and serve.