The U.S. Fish & Wildlife Service's Arctic National Wildlife Refuge (ANWR) Site
This report from the U.S. Fish and Wildlife Service's Alaska offices provides and excellent and thorough overview of the ANWR region, its ecosystems, and what is at stake regarding oil and gas development in the area.
The 1998 U.S. Geological Survey Fact Sheet on Oil & Gas Exploration in ANWR
This 1998 report from the U.S. Geological Survey is the best, and most used, estimate to date of how much oil is thought to be economically extractable from Area 1002 of the Arctic National Wildlife Refuge under the limitations of current and forecasted technologies, and what would be involved in doing so. It contains detailed geological analyses of the region including its plays, structural settings, general geological and physical settings, stratigraphy, the geochemistry of the region, and much more. It also contains an economic analysis of the forecasted costs of development of extraction and transportation of petroleum products from the ANWR region and the methodologies used for all the assessments. The second link is to a general fact sheet which summarizes the high points of this study, including 95 percent confidence, 5 percent confidence, and median extractable barrel estimates.