S.F.
We live in San Francisco and we spent about $1400/month for a full time (7:30-6) licensed family day care from about 3 months to 2 years of age. There, we had to provide all diapers and food (I pumped and so that was much cheaper than formula). Now that dd is in full time preschool (7:30-6) it is a bit cheaper -$980/month and they provide 2 meals and 2 snacks.
I would say that diapers cost about $25-30/month, babies are free the first 6 months if you breastfeed, and I didn't buy hardly any clothes as she got them all either as gifts or hand me downs. Now that she is over 2 I probably spend about $150 every 3-6 months on new shoes and used clothing.