To say it bluntly: Screw family and friends if they will change their opinion of you if you lock your hair. If they care that much about how you look, then they weren't good friends to begin with. Family will always be concerned, but if you explain why you want them, then hopefully they'll understand, and though they might not like them, at least tolerate them because they love you.
As for a job, they should not affect it if you are good at interviews and able to show that you are more than qualified over the other applicants. People here will tell you that you can claim they are protected under the first amendment for religious reasons, and that you can argue your civil rights. It's true, but only if they really do have spiritual significance to you. It's become a trend for people to claim religion to save their locks even if they don't actually believe in anything. All I ask you is to be honest. If you are growing them for spiritual or religious reasons, feel free to boast it if an employer give you grief. But if you are just growing them because you think they are cool and always wanted them, please don't make any such claims. It ruins it for those of us who are.