The Environmental Working Group’s interactive database lets you look up farm subsidies paid by the USDA. You can get all kinds of information–subsidy payments by county or congressional district, top 100 recipients of subsidies, breakdowns into particular types of payments (conservation, crops, disaster, etc.), and so on. It’s an interesting source of information, given that the Obama administration wants to drastically reduce farm subsidies and we’re likely to see a big argument over what the impact will be on farmers. Some groups argue that mid-sized family farms will be devastated by the loss of price supports. Others point out that subsidy payments are highly concentrated, with the top 20% of recipients getting the overwhelming majority of payments, and that if large industrial operations were forced to compete with family farms on an even playing-field without welfare payments, many of them would go out of business, leading to lower production and higher prices for other producers.
This was a big debate among rural sociologists when I was in grad school, and I guess we may be about to see.