I just got a visit visa for my brother yesterday. However, it's a non-extendable one month visa only.
It's pretty easy, go to the Ministry of Interior office just outside the Doha airport, take your passport copy (with the RP page) and your brother's passport copy, and fill the form avaible there. You can fill the form in English, and submit it. They charge Qr 100 for this One month, single entry visa. They will give you a visa tracking number and then you check online at moi.gov.qa and within hours the visa will be ready.

I got the visa within 2 hours of submitting the application. No salary certificate reqd.