I have many tattoos (but none on hands/neck) and pretty long hair. I did have facial piercings which I removed during grad school because people really did not care for the piercings. I've never had the tattoos be an issue in the corporate world. The only person I know with hand tattoos is a software engineer and he is plenty successful. I think if you are good enough at your job and good to work with employers will care about that more.