Attestation from the country where you have studied and got married will be required from the ministry of foreign affairs and also from the state ministry and Qatar embassy. Its better you get it done through an agent as it will be an easy and fast process. If you want you can get it done in Qatar as well as there are some agents here as well (you can search in google), however in Qatar you will end up paying more. once its all done you will then have to get them attested in the ministry of foreign affairs in qatar. if u go by yourself there is a nominal charge of 20QAR.