ProXRS. Click Here.
The best Trimble GPS unit ever made. Accuracy from 50cm to 10cm. Satellite and Beacon differential correction.

Below are the top GPS Web sites on the Internet. You can GPS information, GPS tutorials, and a wide variety GPS references.

U.S. GPS Policy by Presidential Directive
All about the March 29, 1996 policy. Includes a CNN news piece.

U.S. Naval Observatory Time
You can set your time here, learn about GPS timing

The Home for Recreational GPS
The dynamic duo Joe Mehaffey and Jack Yeazel tell all about recreational GPS and what works

University of Maine. GPS Sources
Over 100 GPS, Glonass, Galileo, and Geodesy links.

U.S. Coast Guard Differential GPS
The USCG's radio beacon system and reference locations

Russian GLONASS information
From the Russian Space Forces with Love!

GPS Precise Orbits from NOAA
Precise orbits available two to six days after observation

University of Colorado at Boulder
A Global System overview. Loaded with GPS information and data.

Trimble Navigation
The Trimble GPS Tutorial is worth accessing. In easy to understand terms, Trimble explains GPS. Sections include: Why GPS?, What is GPS? How GPS works in the "5 Steps to GPS", Differential Correction and Putting GPS to Work. Clever animation and illustrations help ease the pain. Just like in the classroom, review questions follow each section.

International GPS Service
Federation of over 200 worldwide agencies collaborating to form a global network of over 300 continuous GPS station.  JPL and NASA operation.