The data from the SDDS is available as a seamless product on the Seamless Data Distribution System see http://seamless.usgs.gov The imagery is available for online download as small files or larger areas may be purchased on media (CD or DVD). Looking for more free resources & FTP sites? Other Sources of Orthophotos & imagery are provide in this list:

http://gisdata.usgs.net
http://www.faygis.org/datasearch.cfm http://www.cast.uark.edu/cast/geostor/raw_DOQ/index.html http://sal.uamont.edu/pages/nsdd/Arkansas_State.htm ftp://ccwgov.co.calaveras.ca.us/GIS/Raster_Data/Aerial_Photos/2002_2ft_Color_DOI/ ftp://ftp.ci.corvallis.or.us/pw/gis/orthophotos/ http://casil.ucdavis.edu/casil/kerncog.org/
http://casil.ucdavis.edu/casil/usgs.gov/ http://www.landwateruse.water.ca.gov/basicdata/landuse/digitalsurveys.cfm http://www.fcgov.com/gis/downloadabledata.php http://www.udel.edu/dgs/dgsdata/hundreds.html http://magic.lib.uconn.edu/cgibin/MAGIC_DBsearch2.plGeography=37811&Loc=0001 http://data.labins.org/2003/MappingData/DOQQ/doqq.cfm ftp://gisftp.hicentral.com/AirPhotoImages/
http://inside.uidaho.edu ftp://itoc.in-span.net/ http://cairo.gis.iastate.edu/map.html
http://gisdasc.kgs.ku.edu/kgcc/
http://gis.sedgwick.gov/view/ http://musashi.ogis.state.me.us/catalog/catalog.aspstate=2&extent=24k http://www.mass.gov/mgis/laylist.htm http://maps.dnr.state.mn.us/deli/data_search.html http://www.lmic.state.mn.us/chouse/airphoto_usda.html http://www.maris.state.ms.us/HTM/DataWarehouse/NAIP.htm http://msdisweb.missouri.edu/data/naip/
http://nris.state.mt.us/nsdi/orthophotos/ ftp://www.co.missoula.mt.us/Surveyor/Horizx/MR_SID/ http://www.dnr.state.ne.us/databank/fsa03.html http://www.dnr.state.ne.us/databank/lanc_doqq.html http://njgin.nj.gov/OIT_IW/index.jsp ftp://ims.bernco.gov/data http://rgis.unm.edu/loader_div.cfmtheme=Digital20Orthophotos http://www.nysgis.state.ny.us/gisdata/ http://lnweb02.co.wake.nc.us/gis/gismaps.nsf http://www.state.nd.us/gis/mapsdata/download/ http://www2.ocgi.okstate.edu/2003img1/ ftp://ftp.ci.corvallis.or.us/pw/gis/orthophotos/
ftp://imagery.pasda.psu.edu/pamap/ http://www.edc.uri.edu/orthosf/orthos/2003usda/ http://www.pasda.psu.edu/documents/datalist.cgi/naip http://www.edc.uri.edu/orthosf/orthos/2003usda/ http://www.edc.uri.edu/orthosf/orthos/2003usda/mrsid.html http://www.sdgs.usd.edu/register/index.html http://www.capco.state.tx.us/Information_Clearinghouse/Orthoimagery_main.asp http://agrc.utah.gov/agrc_sgid/naip.html
http://gis.vcu.edu/datausda.html
ftp://ftp.spokanemaps.com/ http://wvgis.wvu.edu/data/dataset.phpaction=search&ID=254#Download http://edc.usgs.gov
http://nationalmap.usgs.gov
http://www.usgs.gov
http://terraserver-usa.com/

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