Undeveloped or Vacant

Land Watch - Site listing rural land in North and South America.

Land.net - Directory of residential and commercial land for sale or lease.

Private Islands Online - Offers listings of islands for sale or rent in the US, Caribbean, Canada, Oceania, and Europe.

Realtors Land Institute (RLI) - Organization of professionals specializing in land brokerage. Includes details on membership, property search, and an auction calendar.

UK Land Investments Group - Develops parcels of undeveloped land from offices around the globe; includes investment opportunities, market statistics, and news.