Hello Judy -- Sorry this happened to you. In the internet world today I am not surprised. A seller has to apply their best judgment whether placing an ad in your local newspaper or eBay or Craigslist or at Air Forums. Mostly by accident - but just yesterday I discovered a scammer looking at two ads and I emailed warning to the two sellers.
On the classifieds page there is a link to tips and advice on how to work with a sale.
Air Forums cannot mediate sales -- they take place off this site and between the involved private parties. Be wary and alert. Know the high signs of a cashier check scam
Do not reply if you get a suspicious email -- your email is hidden until you reply to them. PM a moderator if you have any questions!