if you are allowed by the labor department to accompany your family in the country,i.e you have permission to bring your wife,you can request the transfer from immigration at the cost of 500QR+ Fees.

This is clearly showing in Immigration office in Garafa in the list of fees, you can ask any of the immigration member of staff and he will tell you.

However, if you are unable to bring your family under the labors law,you are adviced to extend her vsist visa before its due,simply the penalty is big and to my knoweledge around 200 QR/Day or even more