Indeed - after all, at pro tournaments the caddies all have them (and are given updates with pin positions by the organisers each morning), so I'd hope we mere mortals could use them too!
After our club permitted the use of GPS in comps, I used Google Earth & a card of the course to map the course on an old PDA with gps function. Worked a treat, as I could set my own "waypoints" , and only cost pennies.