Ethernet Shield V1.0 for Arduino:http://www.nuelectronics.com/estore/index.php?main_page=product_info&cPath=1&products_id=4&zenid=4f8763dd32227d54ee11ac472d5c09a4
Learning About Arduino Ethernet:http://code.rancidbacon.com/LearningAboutArduinoEthernet
SVN of Ethduino:http://svn.mlalonde.net/Ethduino/