The American Society for International Law (ASIL), with support from the Mellon Foundation, has set up the Electronic Information System for International Law, which can be found at www.eisil.org
The materials include basic legal documents and agreements, research reports, pointers to sites for news and commentary ... it's encyclopedic! And I recommend it highly.
Credit for creating a tremendously useful resource goes to the EISIL authors:
Stephanie Burke - Boston University School of Law, Anne Burnett - University of Georgia School of Law , Marci Hoffman - University of California at Berkeley School of Law, Krista Lindhard - Mayer, Brown, Rowe & Maw LLP, Amy Osborne - University of Kentucky Law School , Gail Partin - Dickinson School of Law, Pennsylvania State University, Dean Rowan - University of California at Berkeley School of Law, Mary Rumsey - University of Minnesota School of Law, Louise Tsang - Georgetown University Law Center, Kelly Vinopal - American Society of International Law, Jill McC. Watson - EISIL/ASIL Guide to Electronic Resources for Int'l Law, Jean Wenger - Cook County Law Library