Try an Agway - Belle Mead Farmers CO-op has it, for example.

The brand of corn gluten I use is called "Safe 'n Simple",
a BLUE SEAL product. Their website (www.blueseal.com) will
undoubtedly have a retail locater - just enter your Zip Code and it will tell you all the stores in your area that
carry their products. From past experience, I've learned
it's best to CALL each location first, just to make sure
they have that specific product you want. . .

Raritan Agway carries it. Thank you!