It was around $210.
Oh dear, I feel kind of guilty now.
In your earlier thread you were asking about a cheap "get me home in an emergency" GPS solution and I suggested the cheapest eTrex (probably in the $40-$70 range) as something that would work.
But $210 would go a long way towards buying a dedicated aviation GPS such as the Garmin 96C. Which will be infinitely more useful if you start to rely on it (eventually) for post-PPL cross countries.
In any case, as others said, don't go inputting waypoints on the eTrex itself. It's too tedious and too error-prone. Use some sort of computer interface that allows you to input/display them on a map somehow. Personally I use OziExplorer but anything that converts to/from Google Earth would work too.