I haven't been doing this that long, but agree with the others. I only use the GPSr to store the waypoints so as I travel I know one is coming up. I then look up the PID on my PDA or laptop or printouts if I am only looking for a few. As far as using the GPSr to find them, it is really an optional tool - not a necessity. As PB stated - I find a measuring tape, prod, garden trowel, camera, and metal detector more valuable. I have found that it is good to take copious notes when you find them (or not) because it is easy to mix them all up when you get back home and go to log them on GC (as I did on MF0209).
Brendan