I used an off the shelf GPS from Trimble and a small single board computer with a 2 line LCD. The connection was via serial ports and the code was trivial.
Are you able to solder wires and write micro controller code?
I have been looking for a handheld GPS device which displays co-ordinates only. These were available years ago (very very expensive) but I cannot find any today.
They should be reasonable with the advances in GPS devices but I cannot fond them at any price.
I might be interested in a unit which has a screen (which would be completely useless and would be nice if it could be turned off to conserve battery) if it has the digital readout.
DOES ANYONE KNOW if such devices are available? if so could you forward information on them.