The USGS Science Data Catalog includes records describing individual datasets, data collections, and observational or remotely-sensed data contained in national systems (rather than records about individual observations). The Catalog does not include USGS data for which there are
currently no online access points.
USGS is covered by Elsevier DataSearch. Another tools to retrieve USGS Data: The USGS EarthExplorer (EE) for aerial photos, elevation data and satellite products http://earthexplorer.usgs.gov/; USGS Global Visualization Viewer (GloVis) for Landsat missions, ASTER and MODIS data holdings http://glovis.usgs.gov/; LandsatLookViewer http://landsatlook.usgs.gov/