When you post anything on craigslist, you have to give your email address. But If you want to post anonymously on Craigslist, and still want some response then you have two options. Firstly, you can use craigslist 2-way email relay, it will help to protect your address as well as an email address of that user who is replying to your post. It also helps to stop all the spams and the response will come into your actual email address. Secondly, you can give your contact details instead of an email address.