Just a quick post but when you are replying to a job posting via e-mail make sure to attach your resume to it. Sending a second e-mail, the same as the first but with the resume attached is a good back up plan. Personally I have not heard back from anyone were I forgot to send my resume with my first e-mail.
Also, I have tried using the BCC options in responding to the craigslist ads that were for the same or similar position title. I did get some responses but it was a pain to figure out what went with what. Also when they did respond most were scams and the others didn't mention craigslist at all. When I tested it to myself it looked kind of obvious that I had e-mailed the same thing to several people. The BCC tag is a bit of a tip-off. Personally I don't know if I will try that method again.