BBB online may have info on ownership status.
If the county government is well-wired, you might get the i.d. of the property owner online (tax assessor).
City or County might have ownership info for a dba online.
State may have ownership info for a corp or other business entity online.
The advertisement seller (newspaper or mag where you found the mail order) might help you with owner info.
Postmaster or FTC will both take complaints, as will the State A-G.