Note that while the Heartland Art webpage links to the site of the Heartland Earthworks Conservancy, a legitimate preservationist group with archaeologists on their board, it is not affiliated with the Conservancy.
If you go to the Book of Mormon Evidence link on the site, you’ll see that the “Heartland” name appears there as well, as part of Mormon apologist Rod Meldrum’s “Book of Mormon Evidence and ‘Heartland’ Research Tours and Cruises” (as he punctuates it). “Heartland” is his brand:
Join the hundreds of LDS faithful who have experienced the ultimate in LDS educational touring - and now CRUISING - with one of the "Heartland" geography's most knowledgable (sic) and enjoyable hosts... Book of Mormon geography expert, researcher, author and lecturer Rod Meldrum. Rod has teamed up with Legacy Tours and Travel and Cruise Lady to share wonderful opportunities to learn about and experience these sacred sites.
According to an email published online, Meldrum claims that God made him abandon his career to devote himself full time to making money by selling materials related to proving the Book of Mormon happened in the United States.
It’s particularly interesting that Meldrum aims his pseudoscience squarely at the interior of the United States, the “heartland,” and he does not hide the fact that his primary audience is nationalist and conservative. Consider this paragraph about his upcoming fifteenth Book of Mormon Evidence Conference, to be held in April. It is a conflation of a number of conspiracy and “prepper” claims popular with the nationalist right-wing fringe masquerading as a celebration of Mormonism:
Overwhelming new evidence from multiple fields is now indicating that the Book of Mormon history took place in what is now the Heartland of America. Entire families can now join in on this incredible learning opportunity with new research and evidences that the Book of Mormon lands were right here on the Promised Land of the United States of America. Over 100 classes are being offered on the US Constitution, health and wellness, preparedness, personal protection, alternative medicines, first-aid, food preservation, gardening and more!
Now here’s where the confounding part comes in: Meldrum’s view that the Book of Mormon takes place in the heartland of America, particularly around the Great Lakes, isn’t held by all Mormons. The Mormons have a range of views, and a large number reject the “heartland” theory for exhaustive reasons. Another is the “Limited Geography Theory,” which holds that the Book of Mormon takes place in Central America. Supporters of the heartland and Central American hypotheses have battled one another for years now, each accusing the other of underhanded tactics, ignorance, fabricating evidence, and general nastiness.