Not only can she not be Australian, she has to be from one of the nations defined (Phillipines, Indonesia, India, Sri Lanka, Nepal, Ethiopia). You both have to be working, except in extreme circumstances. You have to be earning over a certain limit which I imagine you meet. You will probably have to employer as a Maid, the categories are fairly thin on the ground. I think they need to be over 25 as well.

You will both need your RP's in place, a letter of No Objection from your sponsor, 6 months bank statements, Qatari Labour contract, possibly housing contract.