my advice is to go where the people go and hang around sharing great content first. Building a trusted rep is whats its all about. Do not sell. People don't like to be told what to buy no matter how cheap your price are even free they will not touch unless you have thier trust.
Classifieds are dead unless its Craigslist. PPC is expensive but FB is good for it. But the real targeted traffic comes from interaction with people.
Of course you can learn the masters process if you have deep pockets but then again if you are willing to learn.
My tip for the day