i'm very pasionate about this and have learned a bit about it; both my kids were exclusively breastfed w no bottles; nursed my son till 3 and am still nursing my daughter who is 20 months.
first of all you can go to a La Leche League Meeting in your area to learn more about baby nutrition; just google La Leche League Intl. and click on resources to find your local meeting.
but the real news is this; the baby does NOT NEED COW'S MILK. that is a total myth and probably one of the main causes of childhood obesity. remember that cow's milk is a food originally intended for animals who have to gain 400 lbs in the first year of life. and in almost no other culture in the world do people drink cow's milk; where they do, they are fat and have heart disease, like us.
there are many foods with calcium like all kinds of greens; and plenty of lean protiens like legumes and beans and rice and turkey and chicken that you can give very little children.
they do love dairy don't get me wrong; that's another reason i don't give milk to drink; they love thier mac and cheese a couple times a week and my son loves yogurt. so i save the dairy for that and nutritionally that's more than enough. also pizza every couple weeks.
my kids drink water almost exclusviely. and apple cider watered down. that's it. and just to show you that they've lost nothing for this; my daughter is 20 months, runs, swims under water, talks, and weighs 25 lbs, and my son is 3 and 4 months and weight 38 lbs and is the most verbal kid in his school and one of the tallest. so there you go.