Last week Moonrat (an editorial assistant at a publishing house) had a wonderful post on what the hell a publishing platform is and how to go about getting one even if you don't think you know anyone.
I recommend it the article and don't really have anything to add as I'm focusing most of my energy on writing not publishing right now.
Speaking of which ... if anyone has a really fabulous way to teach college students about incorporating citations in research writing let me know, because I really don't remember how I learned to do that myself. I think it was just a really gradual hit or miss process for me ... which doesn't translate well into a lecture.