Landsat Data Resources
http://landsat.gsfc.nasa.gov/main/data.html

NASA


This site from NASA provides a number of resources for obtaining Landsat digital data. Included are links for ordering Landsat 7 data as well as sources of Landsat 4, 5 and other related and heritage land remote sensing data.

This resource is referenced here:
Subject: Geography:Geospatial, Geoscience:Geology
Resource Type: Audio/Visual:Animations/Video, Maps, Scientific Resources:Collection, Datasets and Tools:Tools, Datasets, Audio/Visual:Images/Illustrations
Data Derived: Data Derived
Data Source: Observational Data
Earth System Topics: Human Dimensions, Surface Processes
Science Background Required: Basic scientific background required
Topics: Earth surface