Nanshi Food street should be the most well-known place for eating in Tianjin. Foods can also be found in Zhongshan Road, Binjiang Dao. Those are in the city center and a bit far from the airport, but I still suggest you take a taxi to the airport. It takes no more than 100RMB, and less than 25RMB for each of you. It is resonable and easy. With a hotel, I think Home Inn and 7-Days Inn nearby Zhongshan Road are fine. They are buget chain comfortable inns. You can share room with friends.