ASRS Aviation Safety Reporting System.  Keep a form handy.

Aviation Digital Data Service  NOAA WX site.

AvWeb Great GA site.  Subscribe to their spiffy newsletter for free.

C&P Press The Greenbook

FAA Civil Aviation Registry

Junkscience.Com "All the junk that's fit to debunk." Interesting FAQ on DDT.

National Agricultural Aviation Association

Sky-Tractor Distributors of PC Spray.

Trade-A-Plane Online