Hi Ibrahim,
You must hold RESET low to use the serial interface. If RESET is held high then the output format will be based on the DFS pin. You must also either pulse the RESET pin or use the software RESET (Reg 0x00) to reset the registers. You can then program the registers. Your register settings look fine. CLKOUT should be on pin 5 in CMOS mode.
You must apply a clock to the ADC in order to get the clock out. You seem to indicate that this was done.
Another thing to look at is to make sure your SPI interface is working correctly. Try to probe the SPI signals and verify that the data is what you expect.
Regards,
Matt Guibord