If you have friends and/or family, but no money, you rely heavily on hand-me-downs. An example of ours -- although cloth diapers are cheaper in the long run than disposable diapers, the start-up costs are steep. But we've had to buy less than 1/5 of the cloth diapers we've used, because they pass through a loose network of friends.

If you don't have friends or family, the only money saving option really available in the US (that I know of) is used/thrift shops and consignment sales.