One of my favorite Italian restaurants in Park Slope, Brooklyn is Fornino, located on 5th Avenue between Carroll and Garfield Place.
They offer an assortment of gluten free pastas and pizzas. The pasta they use is made out of corn flour and the pizza dough they use is made out of brown rice flour. I've tried both the pasta and pizza and they are excellent!
As far as the pasta, I've had the penne pesto primavera (see photograph) and as for pizza, I've had the margherita classica pizza.