My friend this is the way how to obtain a tourist visa.
Go to the Airport Immigration (timing 7 am - 2 PM)
Bring with you:
your passport copy
ID copy
passport copy of the visitor

Fillup a form (Tourist visa form)available in the counter and attached the requirements above then proceed to a room where the Captain is seeting and obtained his approval, once he signed the form proceed to counter Nos. 6 - 10 for processing of visa and pay QR. 100 by an ATM and the teller will issue a receipt for printing of the visa from the website of MOI after 1 or 2 days.

Hope this helps..