What are the qualifications for a home owner's loan?

I'm expecting my first child in January 2012. My current income isn't enough to afford a home. So I was thinking of taking out a loan for a home. I don't have any credit cards, so I guess I don't have a credit score. My plan is pay out the loan monthly according to my income. So what are the qualifications for a home owner's loan? Please specify. Thanks! :)