Easy.

1) minigpsd on the Nxxx
Log the GPS location to a file - it will make KML, but I don't know if it does other formats.

2) gpsbabel on the Nxxx or PC
Convert the KML file to a more suitable format (probably GPX).

3) gpicsync on the PC
Geocode photos using the GPX file

I used to do this all the time (but not with gpicsync) but then got fed up of all the hassle and bought a GPS unit for my Nikon DSLR.