Trees for the Future - http://www.treesftf.org - Trees for the Future is a non-profit organization initiating and supporting agroforestry self-help projects in cooperation with groups and individuals in developing countries.
Precision Planting - http://precisionplanting.com - Offers implements and training for precision farming, including Keeton Seed Firmer planter attachment, the Meter Max calibration system, and training videos.
Precision Farming - http://www.precisionfarming.com - General information on precision farming and other advanced agricultural technology, plus online Farmnotes, message board, and buyer's guide.
Precision Agriculture in the High Plains of Texas - http://precag.tamu.edu - Publications and information about Texas Agriculture Experiment Station research on crop spacing, improved irrigation management, use of remote sensing data in controlling irrigation and chemigation, and other precision agriculture applications.