Sintron] UNO R3 board with Ethernet Shield W5100 + PDF for Arduino AV – Sintron Technology
Amazon.com: Mini W5100 LAN Ethernet Shield Network Board Module for Arduino R3 W5100 3.3V Compatible for Arduino Ethernet UNO Mega 2560 : Electronics
Amazon.com: DEVMO W5100 Ethernet Network Shield LAN for Ar-duino Expansion Board Module with SD Card Slot Compatible with Ar-duino UNO MEGA2560 UNO R3 ATMega 328 MEGA 1280 : Electronics
Arduino UNO Compatible Ethernet Shield - PiShop.us