For overviews of American seacoast defenses you can consult these published works:
Lewis, Emanuel R. Seacoast Fortifications of the United States, an Introductory History, Naval Institute Press, Annapolis, MD 1970, 1992.
Kaufmann, J.E. and Kaufmann, H.W. Fortress America The Forts that Defended America, 1600 to the Present. Da Capa Press, Cambridge, MA 2004.
Floyd, Dale E. Defending America’s Coasts 1775-1950, Office of History, United States Army Corps of Engineers EP 870-1-57, Alexandria, VA, Government Printing Office, Washington, DC, 1997.
For overviews of the earlier American defenses (1794-1876):
Wade, Arthur P. Jr. Artillerists and Engineers, the Beginnings of American Seacoast Fortifications 1794-1815. CDSG Press, McLean, VA 1977, 2010
Weaver, John R. Jr. A Legacy in Brick and Stone, American Coastal Defense Forts of the Third System, 1816-1867. Pictorial Histories Publishing, Co. Missoula, MT 2001.
Williford, Glen. The Transitional Coast Defense Generation, American Seacoast Defenses of the 1870s. Coast Defense Journal Volume 21 Issue 3 (August 2007) pp. 51-84.
Williford, Glen. American Seacoast Defense Sites of the 1870s: Part 1, Coast Defense Journal V20, Issue 3 (2007) pp-51-93.
Williford, Glen. American Seacoast Defense Sites of the 1870s Part 2 Coast Defense Journal Volume 21, Issue 4 (2007) pp. 59-110.
For an introduction to the post-1900 American seacoast defenses:
Berhow, Mark A. ed. American Seacoast Defenses, A Reference Guide. Second Edition, CDSG Press, McLean, VA 2004.
McGovern, Terrance, and Smith, Bolling. American Coastal Defenses 1885-1950. Fortress Series #44, Osprey Publishing LTD., Osceola, WI, 2006.
Zink, Robert D. The Six-Inch Part of the Modernization Program of 1940. CDSG Journal Volume 8, Issue 2, May 1994.
Mark Berhow. America’s Last Seacoast Defenses: the World War II – Era Construction Programs. CDSG Journal Volume 8, Issue 4, November 1994, p. 34
Mark Berhow United States Seacoast Batteries Built or Modified During the Years 1935-1945. CDSG Journal Volume 8, Issue 3, August 1994, p. 32.
CDSG Press Reprints of key US Coast Artillery reports, books and manuals:
Notes on Seacoast Fortification Construction, by E.E. Winslow, Occasional Papers No. 61, Engineering School, United States Army, Govt. Pub. Office, Wash. DC 1920, reprinted CDSG Press, McLean, VA, 1994.
The Service of Coast Artillery, by Frank T. Hines, and Franklin W. Ward, Goodenough & Woglam Co., New York, 1910, reprinted by the CDSG press, McLean, VA, 1997.
American Coast Artillery Materiel (Ordnance Department Document No. 2042), Govt. Printing Office, Washington, D.C., 1923. Reprinted by the CDSG Press, McLean, VA, 2001.
Seacoast Artillery Weapons, Technical Manual 4-210, War Department, Govt. Printing Off., Washington, DC, 1944, reprinted by the CDSG Press, Bel Air, MD, 1996.
Permanent Fortifications and Sea-Coast Defenses, 37th Congress of the United States (1862), Congressional Report No. 62, U.S. House of Representatives Report of the Committee on Military Affairs. (House of Representatives Report No. 86) Reprinted by the CDSG Press, McLean, VA, 1998.
The Endicott Board Report (1886), the Taft Board Report (1906), and the Board of Review Report (1915). Proper titles are: Report of the Board on Fortifications or other Defenses Appointed by the President of the United States under the Provisions of the Act of Congress Approved March 3, 1885, House Executive Document No. 49, 49th Congress, 1st session (GPO, Washington D.C.,1886); Report of the National Coast Defense Board . . . on the Coast Defenses of the United States and the Insular Possessions, Senate Document No. 248, 59th Congress 1st Session (GPO, Washington D.C., 1906); Report of the Board of Review of the War Department to the Secretary of War (November 26, 1915) on the Coast Defenses of the United States, the Panama Canal, and the Insular Possessions, House Document No. 49, 64th Congress, 1st Session (G.P.O., Washington D.C., 1916). reprinted by the CDSG Press, McLean, VA, 2007.