Data Products

No. A photographic enlargement only appears to show more detail than a 9-by-9 inch photograph. Photographic resolution (or image resolution) deteriorates with each enlargement factor.
YES, Visit our National Geospatial Program page or call 1-888-ASK-USGS for our information package on digital cartographic data. 
That depends on what kind of reprojection you want to do. In some cases, if you want to reproject from one datum to another (specifically NAD 27 to NAD 83, or NAD 83 to NAD 27), a simple x-y shift will suffice.
Hydrography data from the NHD are offered in Esri File Geodatabase 10.1 or Shapefile formats.
For the conterminous United States, Hawaii, and the U.S. Virgin Islands, medium and high resolution NHD data are available at 1:100,000 and 1:24,000 scale, respectively.
It will probably take approximately 5 years to digitize the archive. A priority scheme is being developed and will be made available to the public at a later date.
USGS Digital elevation models (DEMs) are arrays of regularly spaced elevation values referenced horizontally either to a Universal Transverse Mercator (UTM) projection or to a geographic coordinate system.
The public may download digital aerial photography products at no cost from the Earth Resources Observation
The aerial photographs date as far back as the 1940's for the United States and its territories. Availability of specific coverage, film type, and acquisition dates vary from agency to agency.
We generally emphasize the following four points: