GPS Tools for Diving

Free GPS software to manage your hand held:
easygps.com

divespots.com
A very neat web site that is a community run database of diving locations: dive site info/history, photos, reviews, maps, and the best part? Downloadable GPS data to help you find it! Pretty rad.

You might need a serial-to-USB cable to connect your GPS to your compy:

Sabrent USB to Serial Adapter from TigerDirect