Find your heat and hardiness (cold) zones. You can even find your soil zone here as well as historic weather data.
Official website of CoCoRaHS providing info on the organization and weather and climate data collected by volunteers all over the country. Some AAEMG members participate in this activity.
An archive of climate data, maintained by the National Oceanic and Atmospheric Administration (NOAA)
Get a soil survey map of specific areas of the country using this website
Climate zones used by Sunset in its gardening publications which are popular in the SW.