Foster-adopting a newborn?

My husband and I want a baby. As far as we know, we are able to have one biologicaly, we haven't tried to conceive yet. If there are babies available in the foster care system, we would prefer to foster-adopt than have our own baby. We just feel so strongly about giving homes to children who are already here. If we choose to have our own baby first, we will definitely be foster-adopting future children. We are just trying to decide what to do about our first. We would prefer a newborn. My question is, has anyone had success foster-adopting a newborn? Are there babies available for foster-adoption or is it mostly older children and siblings? We are open to that in the future, but at this time we want a baby. Also, are there any blogs available about foster-adoption that I can read to get more of a feel for it? Thank you! :)