He lives in Ballston Spa, New York.
(I may be taking a risk, but I DID find a couple of sources - Whitepages and Instant Checkmate - that implied he was alive. Only strange thing is, they said he's still 89!)
He's illustrated books by Rudyard Kipling and William Jay Smith, among dozens of others.
http://www.vintagechildrensbooksmykidloves.com/2012/01/wartville-wizard.html
("The Wartville Wizard." "An old man fights a town of litterbugs by magically sending each piece of trash back to the person who dropped it.")
http://www.cbkassociates.com/abcd-books/catalogue/the-wartville-wizard/
(Don Madden tells the story behind that book)
The only other book he wrote was "Lemonade Serenade."
https://www.google.com/search?q=%22don+madden%22+illustrator&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjT09y4rvDWAhWHQyYKHfkpCXUQ_AUICigB&biw=1266&bih=779
(book illustrations)
https://www.pinterest.com/pin/165859198750886808/
(more - this includes the work of other illustrators)
http://www.vintagechildrensbooksmykidloves.com/2014/07/the-sun-our-nearest-star-don-madden.html
(a few more)
https://www.google.com/search?biw=1266&bih=810&q=%22Don+Madden%22+kirkus&oq=%22Don+Madden%22+kirkus&gs_l=psy-ab.3..33i160k1l2.1964.3083.0.3298.7.7.0.0.0.0.125.723.1j6.7.0....0...1.1.64.psy-ab..0.7.720...0j0i67k1j0i22i30k1.0.QnssLfMW0r8
(a few Kirkus reviews)
https://www.kirkusreviews.com/book-reviews/ea-hass/incognito-mosquito-private-insective/
(review of "Incognito Mosquito")
https://www.goodreads.com/author/show/163900.Don_Madden
(reader reviews)
http://bubuchildrenbooks.com/doctor-leos-pet-patients/
(about "Doctor Leo's Pet Patients" - includes environment issues)
http://www.vintagechildrensbooksmykidloves.com/2010/02/daddy-book.html
("The Daddy Book")
http://www.threebooksanight.com/book-reviews/the-daddy-book-stewart-don-madden/
(more on that one)
http://www.vintagechildrensbooksmykidloves.com/2010/10/one-kitten-for-kim.html
("One Kitten for Kim")
About "Nothing Much Happened Today": "Three children, Stephen, Elizabeth, & Alan, try to explain to their mother Mrs. Maeberry, the chain of events that brought havoc to the household during her twenty minute absence."
https://www.google.com/search?biw=1266&bih=779&tbm=vid&q=%22Don+Madden%22+book&oq=%22Don+Madden%22+book&gs_l=psy-ab.3..33i160k1.10544.11262.0.11560.5.5.0.0.0.0.102.468.2j3.5.0....0...1.1.64.psy-ab..0.5.465...0j0i30k1j0i8i30k1j33i21k1.0.QpGlNjoEmls
(a few videos about Madden's books)
WRITINGS BY THE AUTHOR:
* (Self-illustrated) Lemonade Serenade (juvenile), Albert Whitman,
1966.
* The Wartville Wizard, Macmillan (New York), 1986.
Illustrator:
* H. Allen Smith, Let the Crabgrass Grow, Geis, 1960.
* Hector H. Lee and Donald Roberson, Lore of Our Land, a Book of
American Folklore, Harper, 1963.
* Mary C. Austin and Queenie B. Mills, The Sound of Poetry, Allyn
& Bacon, 1964.
* Donald Barr, Arithmetic for Billygoats, Harcourt, 1966.
* William D. Sheldon, Nellie Lyons, and Polly Rouault, The Reading
of Poetry, Allyn & Bacon, 1966.
* Ernestine Beyer, The Story of Lengthwise, Follett, 1967.
* Paul Showers, A Drop of Blood, Crowell, 1967.
* Judy Hawes, Why Frogs Are Wet, Crowell, 1968.
* Rudyard Kipling, The Elephant's Child, Columbia Book & Record
Library, 1968.
* William J. Smith, Around My Room, Columbia Book & Record
Library, 1968.
* William J. Smith, Laughing Time, Columbia Book & Record Library,
1969.
* William J. Smith, Grandmother Ostrich, Columbia Book & Record
Library, 1969.
* Gloria Miklowitz, The Parade Starts at Noon, Putnam, 1969.
* Patricia Lauber, Curious Critters, Garrard, 1969.
* Robert Stewart, The Daddy Book, American Heritage Press, 1972.
* Harold Longman, The Castle of a Thousand Cats, Addison-Wesley,
1972.
* Rudyard Kipling, How the Whale Got His Throat, Addison-Wesley,
1973.
* Mary Christian, Nothing Much Happened Today, Addison-Wesley,
1973.
* Sally Cartwright, Sand, Coward, 1975.
* Christian, No Dogs Allowed, Jonathan, Addison-Wesley, 1975.
* Jeannette Bruce, Judo: A Gentle Beginning, Crowell, 1975.
* Norman Smith, Sun Power, Coward, 1976.
* Burton and Rita Marks, Give a Magic Show!, Lothrop, Lee &
Shepard (New York), 1977.
* Judith L. Gersting, Yes-no, Stop-Go: Some Patterns in
Mathematical Logic, Crowell (New York), 1977.
* Paul Showers, Me and My Family Tree, Crowell (New York), 1978.
* George Sullivan, Run, Run Fast!, Crowell (New York), 1980.
* Eve Bunting, The Skate Patrol, A. Whitman (Chicago, IL), 1980.
* Franlyn M. Branley, The Planets in Our Solar System, Crowell
(New York), 1981.
* Mary Blount Christian, Two-Ton Secret, A. Whitman (Chicago, IL),
1981.
* Norman F. Smith, Wind Power, Coward, McCann & Geoghegan (New
York), 1981.
* Christian, The Green Thumb Thief, A. Whitman (Chicago, IL),
1982.
* Edward R. Ricciuti, How to Box: A Guide for Beginners, Crowell
(New York), 1982.
* Sullivan, Quarterback, Crowell (New York), 1982.
* Haas, E.A., Incognito Mosquito : Private Insective, 1982
* Bunting, The Skate Patrol Rides Again, A. Whitman (Chicago, IL),
1982.
* Christian, The Undercover Kids and the Museum Mystery, A.
Whitman (Niles, IL), 1983.
* Branley, Is There Life in Outer Space?, Crowell (New York),
1984.
* Sullivan, Pitcher, Crowell (New York), 1986.
* Sullivan, Center, Crowell (New York), 1988.
* Branley, The Sun, Our Nearest Star, Harper & Row (New York),
1988.
* Kelly Goldman and Ronnie Davidson, Sherlick Hound and the
Valentine Mystery, A. Whitman (Niles, IL), 1989.
* E. A. Hass, Incognito Mosquito Flies Again!, Bullseye Books (New
York), 1990.
* Melvin and Gilda Berger, Telephones, Televisions, and Toilets:
how They Work and What Can Go Wrong, Ideals Children's Books
(Nashville, TN), 1993.
Lenona.