Be prepared for the standard interview questions and know your answers to them. Be prepared to answer that killer question. Know how to deal with illegal questions tactfully during the interview. Prepare questions you wish to ask-only ask questions you can't find answers to yourself. Line up your references in advance and verify that they will be good ones.
Presentation Find out the standard dress for the organization.
Dress on the conservative side. Bring extra resumes, notepad, pen. Be sure you know how to pronounce your interviewer's name correctly. Be polite to everyone you meet there. They all count.