I did it in the past, but keep in mind the GPS has an accuracy of about 6 meters. To enter coordinates, just do it the normal way, but instead of an address, choose 'coordinates' on the next menu page (I don't know exactly where it is, but it's somewhere).
if you are familiar with installing other programs on your device, try beelinegps. works similar to hand-held gps units. i get accuracy to about 3-5 meters usually. i use in conjunction with igo8 (which does pretty well itself at about 5-6 meters accuracy, depending on satellites). igo8 gets you there by road very nicely. change to pedestrian, uncheck auto route recalculation and uncheck keep path on road. also uncheck the warn if too fast for a pedestrian box under warnings. i have a nice hand-held magellan to compare to and both programs were surprisingly decent concidering it was on an automotive unit.