Part of my part-time activities include buying and selling antiques, and selling some extra season tickets. So I legitimately deal on Craiglist often. This is also one place my wife advertises her estate sales for her own business. We follow a couple rules: always use the encrypted craigslist email addresses, request and offer real email addresses only after some trust with a contact is established, we don't reference our phone numbers or home address, and we completely ignore generic responses that don't reference the items involved, or want some extreme favor. And we do the wise bit about meeting near police or fire stations, when needed.
Lastly, and I don't think this was mentioned: if you ever sense trouble or danger on anything over the internet, reference IC3 and this website:
http://www.ic3.gov/default.aspx
Check it out, just for your own awareness. I don't know how backed up they might be, but reference to them is a strong tool. Someone once started harassing me with some messages regarding some concert tickets I was looking to buy. Have no idea why. I sent him the IC3 website, and reminded him that law enforcement officers usually don't take games lightly, but he was welcome to test that if he wished. Last I heard from him. IC3 should be a good reference to provide to any potential scammers in the US, but probably won't work as well on overseas contacts.