Useful links and resources for South America

The South American Explorers Club.

A very useful organisation to help with pre trip planning and logistics. Don't flinch at the hefty membership fee - it more than pays for itself with discounts for hotels, tours (including the Inca Trail) etc. Very highly recommended - particularly for Peru and Ecuador.
If you have access to usenet we would both recommend this newsgroup. Most questions are quickly answered in a responsible and informative way. Your ISP should have details on how you can connect to usenet.
Excellent travel resource which sets out to inform rather than try to sell you insurance and suchlike. Highly recommended.
Worldwide travel directory with links to tourist information, airline, cruises, car rentals, tours, hotels, and other accommodation. Good links site - a good place to start research.