I bought the Garmin etrax GPS unit from amazon. I think it is not the latest and greatest model and therefore inexpensive – on sale for under 90 bucks! Works fine and accuracy seems to be between 15 and 40 feet depending on location. I also downloaded the TerraBrowser, a program for Mac that interfaces with the USGS maps of the USA and shows you exactly where the Waypoint is – on a topo map or a satellite photo. Very useful for those of you who will participate in our GeoCache game this Summer. I am sure Google can help you find PC equivalent software.