geodata.gov – Your One Stop for Finding and Using Geographic Data
http://geodata.gov/

geodata.gov will help you: a) Find Data or Map Services, b) Make a Map, c) Browse Community Information, d) Cooperate on Data Acquisitions, and e) Publish your Data and Map Services. Save searches, maps, and your favorite geography to re-use later. A simple registration process opens up these personalization options. They invite you to explore … or check out their Quick Start Guide to learn more about using the main features of geodata.gov. This has been added to the tools section of Research Resources Subject Tracer™ Information Blog.