You can obtain (via bulk download) the last released 2008 files here for free from Cornell University, Ag-Analtyics.Org
There is a readme in that directory with other info as well.
We also have them available for query via our API. Please contact us at email@example.com if you want to access them that way.
Here are the citations to include please:
"FSA Common Land Units obtained via Ag-Analytics.Org (Woodard,2016a; Woodard, 2016b)" or similar with the following references:
1.) Woodard, J.D., “Big data and Ag-Analytics: an open source, open data platform for agricultural & environmental finance, insurance, and risk,” Agricultural Finance Review, (2016) 76(1):15-26. 2.) Woodard, J.D., “Data Science and Management for Large Scale Empirical Applications in Agricultural and Applied Economics Research,” Applied Economic Perspectives and Policy, (2016) 38(3): 373-388.