Yeah, I always do. Makes it easier for all involved. Just email the HR people or whomever invited you for an interview saying something like 'Just to let you know, I have a bit of stutter, especially when meeting people for the first time. But once we start talking I'll be more fluent. I thought it best to bring this to your attention for the interview.' This will help the interviewer out, too, as part of their job is to calm candidates down so they can pick the best candidate from the stress of interview. HR people know that many really good workers don't interview well and many bad workers interview very well so they work hard to ensure the interview works well for all so they can sift out the best employees. Letting people know you stutter will be helpful for them. For reference, I used to hire IT people for many years.