Booking Flights On-line Help!

Hi guys. I have been trying to book a flight on line from Benin City to Lagos one way. I have been to Arik and Aero sites but the interface is not user friendly and the aero site wouldn't go beyond a certain stage. 

Can anyone please tell me the cost of a flight booked on-line from Benin to Lagos on either Arik of Aero and the cost if I book over the counter.

Thanks.