http://www.landtrustalliance.org - The Land Trust Alliance is the national convener, strategist and representative of more than 1,700 land trusts across America.
http://www.rilandtrusts.org - The Rhode Island Land Trust Council is a coalition of the state's land trusts -community-based organizations formed to protect land that preserves the open spaces, natural areas, scenic character, farm lands, forests, historic sites, watersheds, and drinking water supplies that define the character of our communities and our state.
http://www.privatelandownernetwork.org - The Private Landowner Network provides information about conservation opportunities that can assist you with land management, capital preservation, and tax & estate planning strategies designed to stimulate land conservation & preservation. From the basic concepts to in-depth articles or finding appropriate qualified professional assistance for your needs/circumstances, PLN has the resources you need. Learn about, connect with, and navigate your conservation related opportunities.
http://www.irs.gov/charities/article/0,,id=137244,00.html - This article by the IRS provides information on the tax benefits of donating land.