I was right there with you at 16. Luckily, my first "job" was working at an auto shop for a relative, just doing grunt/gopher/fetch the morning coffee work. I'd get nervous all morning just about having to read out the order to the coffee shop people, as you could expect. Eventually, I dated the hottest girl at that coffee shop. Now I've been working as a journalist for the last 5-6 years. At 16, I never thought I could do a job that centred around speaking. There's no good advice besides you just have to put yourself out there as much as it hurts. Get burned, get burned, get burned until it doesn't hurt anymore. You're not going to get anywhere hiding. I used to hide. Stuttering can't hurt you. If you'd like to talk further, I'm writing/speaking about stuttering a bit on my personal site www.burningstew.com.