A Google search brings up www.evapo-rust.com, which lists dealers and a
prominent notice that the product is carried at AutoZone stores. A number
of mail-order sources are also listed.

It's not clear whether or not this is the same product touted at
www.evaporust.com.  The product name is the same (with hyphen) but the
company names are different.
  [ See Craig Smith's note below for the explanation of the two
  [ slightly different names and two different websites.
  [ -- Relief Editor.

Cheers,
Roger Wiegand
Wayland, MA
www.carouselorgan.com