Lat/Lng to Census Block via FCC
http://data.fcc.gov/api/block/2010/find?latitude=$latitude&longitude=$longitude&showall=true&format=JSON
Did you do actual coordinates or just click the link?
Josh Luthman
Office: 937-552-2340
Direct: 937-552-2343
1100 Wayne St
Suite 1337
Troy, OH 45373