Just saw the second part of your question about applying for visit visa online.

Currently you cant do it online.

You can apply online for Tourist visa online through www.gov.qa . you need to be registered to use the service. You may register online and there is a verification process where you need to go to a nearby post office for identity verification. After that only will your account get active (unless you have the new smart card ID)

regards
iphonewb