There's an article by Wilson Faude in WINTERTHUR PORTFOLIO 10 (1975) that
would probably be useful to you, and of course, Faude's 1978 book on the
restoration of the Hartford house. There are also 15-20 guides to historic
homes that include Twain's house and some discuss it in context with others.
Quality and content varies wildly--

Bacon, Edwin. Literary Pilgrimages
Bass, Geri US Guide to Lit Landmarks
Benedict, Stewart Lit Guide to US
Burke, Michelle Ideals Guide to Lit Places
Eastman, John Who Lived Where
Ehrlich, Eugene Oxford Illus Guide to Homes & Museums
Gilder, J L Authors at Home,
Haas, Irvin Historic Homes
Halsey, Francis Authors of Our Day
Harkins, E F Little Pilgrimages
Kraft, Stephanie. No Castles on Main Street
etc, etc

Kevin Mac Donnell
Austin TX