I was just there in the spring of 2013. Alex Diaz cell: 53021853 is a tour guide and works with cruisers in the marina Hemingway. He looks after peoples boats when they explore inland. He is also on Facebook.
Alex's email is alexcowboyguide "at" yahoo "dot" com he helped us out with everything. Provisions, repairs, translating, restaurants off the beaten path... You name it. He lives right by marina Hemingway and is always willing to help.