After a quick hello/introductions I just start with "oh by the way, I stutter. It shouldn't have too much of an impact on this job, but thanks for your understanding". If I block on my name I say "Don't worry, I didn't forget my name" or something funny like that. People are sometimes curious to learn more so I let them know that they can ask me any questions they want or to repeat myself if they didn't get something I said.