A USB UART/TTL device can be used if wireless is not going to be used. If seeking a wireless solution the hardware being considered must be capable of supporting 9600 kbps No parity, 8 bits and 1 stop bit. Connection to the EZ-B consists of power (+5 vdc and Gnd) and a ttl comm (Tx and Rx). Wireless solutions could be any device that will work with the EZ-B comm requirements. Bluetooth (Class 1 330 ft) XBee, Zigbee,, WiFi, and TCP/IP.

You have one tutorial to plug shield WiFi in Ez-Robots?

I have no tutorials but you can search the forum for info. There is no "Shield" just the WiFi with built in TTL interface that can connect to the EZ-B.

Got it,

You can connect the ez-robot using this TTL.

http://dx.com/p/nt-r02bl-wireless-high-frequency-receiving-module-150634

I want to connect it to the Internet. Is possible?

First step will be to determine what equipment you want to use to connect the EZ-B board to your Robot. After that then you can seek information about how to use the internet to access the EZ-B.