Is it possible to connect Xbee module (Using Xbee shield) as well as Bluetooth module at the same time to any of the Arduino boards like Uno? Most of the sites give information about connecting one module at a time to Arduino boards.
Yes, but the Uno only has one UART. You have to communicate with the Bluetooth module via the Software Serial Library on some appropriate GPIO. The XBee shield could of course also use the Software Serial Library if it is removed from the Uno and attached with wires to the appropriate Uno GPIOs.