The easiest and safest way to sell photography equipment is to sell it to people you know! I've had the good fortune to be able to do this in the past. Failing that, I've also sold stuff on eBay and not had any problems. You only ship when the buyer's funds are in your paypal account, and using an insured & signed for delivery system prevents them from claiming they never received the goods. I'm not an eBay expert but it seems relatively safe these days and gives you access to a very large market. 

With any service you have to use your wits to spot potential scams, it's usually fairly easy to tell if someone's a photography enthusiast or not. I would recommend selling to those who are! 

Remember, the scare stories you hear are always the exception to the norm, "man doesn't get ripped off on eBay" isn't as newsworthy!