Geotagalog makes it easy to geotag photos to a tracklog as you import them into iPhoto.

If you have a handheld GPS receiver, Geotagalog will let you take full advantage of the Places feature in iPhoto '09 with any digital camera supported by OS X. Geotagalog uses advanced geotagging technology to combine a GPX tracklog file with the pictures on your camera, in a straightforward and intuitive workflow.