Internet/Mobile shop near Pontedera/Pisa/Empoli

Hello! New user.I'll be on holiday next week and would like a SIM for internet access. I've previously used a Wind one, so I'm not anticipating any technical problems(!) but I haven't located any likely-looking shops via Google or Pagine Gialli.I'll be staying in Chianni -- my nearest town with assorted shopping would be Ponsacco. It's a few years since I've been travelling around that area, although I do remember the major locations. Steve