In a small saucepan, combine the sugar and water and bring to a simmer over moderate heat, stirring to dissolve the sugar. Let the simple syrup cool to room temperature.
In a food processor, puree the tomatoes and strain the puree through a sieve into a pitcher; discard the solids. Add the simple syrup, lemon juice and ice water and stir.
Fill 10 tall glasses with ice. Pour in the tomato lemonade, garnish with lemon wedges and herb sprigs and serve.