This list starts with a group of general archives then provides more detailed listings for specific developments in alphabetical order, by state and then place, providing links to documents or information on where the archive is located.
National Trust Library Collection at the University of Maryland. Contains planned community section described at http://www.lib.umd.edu/NTL/gardencities.html and http://www.lib.umd.edu/NTL/postwar.html. Links to other collections are at the bottom of each page.
Planned Communities Archives at the George Mason University contains several collections. It is focused on Reston Virginia but is more expansive than that would indicate: http://furbo.gmu.edu/sca/vifgm00006.xml
The International New Town Institute, based in Almere, The Netherlands, has a web site that provides links to various collections including some in the United States: http://www.newtowninstitute.org/spip.php?article48
Civano/Tucson: Civano Neighbors web site includes archives for some neighborhoods as well as a number of reports: http://www.civanoneighbors.com/nav/civano.htm
Sun City: The Sun City Visitor Center provides links to local history documents: http://www.suncityaz.org/history.htm
Baldwin Hills Village/Village Green: The Village Green Owners Association stie contains some historical information: http://villagegreenla.net/history.html. Other documents include: www.tclf.org/landslide/2006/baldwin_hills/site_profile.pdf and Cornell University, Division of Rare and Manuscript Collections, Clarence Stein papers, 1905-1983: http://rmc.library.cornell.edu/EAD/htmldocs/RMM03600.html
Davis, Village Homes: The Village Homes web site has information and links to publications: http://www.villagehomesdavis.org/public/print_web. Other information is at the Local Government Commission http://www.lgc.org/freepub/land_use/models/village_homes.html and http://www.acfnewsource.org/science/eco_homes.html
Irvine Ranch: The University of California, Irvine, has archives on the Irvine Ranch in the university archives, special collections, and the government collection (in print). The Online Archives of California guide to the Irvine Ranch focuses on how the University of California, Irvine, which is part the development as well as the agricultural aspects of the Ranch: http://oac4.cdlib.org/search?developer=local&style=oac4&query=Irvine+Ranch&x=26&y=9
Mission Viejo” Online Archive of California, Mission Viejo Heritage Committee Planned Community Collection: http://oac4.cdlib.org/findaid/ark:/13030/kt2x0nc5xg?query=Mission%20Viejo. This link provides a guide to availability in several collections.
Rossmoor Leisure World (Laguna Hills) : Leisure World Historical Society of Laguna Hills, 23522 Paseo de Valencia, PO Box 2220, Laguna Hills, CA 92653 (714) 951-2330.