bushtrax.com is a collection of 4wd tracks in the state of Western Australia.The information has been collected using a GPS and Oziexplorer. The purpose of this website is to provide fairly accurate information about the tracks within Publicly accessible National Parks etc.
A lot of the tracks cover the coastline and sourcing the latest tidal information is a good idea as beach driving can be hazardous at the best of times. You do not need a highly modified 4wd to experience these places just the right recovery equipment and the knowledge to use it.
You can download the GPS files in a variety of formats and editing and building a file for your brand of GPS is recommended as the way they display a file varies considerably between models.