If you are looking for a guide on Amistad give Olin a shout at Jensens Guide Service. He is a new guide down there but isnt new to fishing the lake. He is a top notch guy that likes to have a good time and he will take care of you. He is a USCG Captain with the required permits and insurance.
He is still working on his website but he has the basic info on there now at
www.jensensguideservice.comAlso, like his facebook page at http://www.facebook.com/pages/Lake-Amistad/380711075277131#!/pages/Lake-Amistad/380711075277131?sk=wall