Any agent can help you too. There are many homes listed on the multiple listing service that are lease with option to buy. That seems to me to be a lot safer than Craigslist, because when done through a realtor, you will get a title report, everyone signs with a notary, and it is all on a contract. Call if you still need help.
Due your homework on these and make sure you're talking to the right owner on record! I've seen some scams on Lease to own deals where people aren't the legal owners. Get someone to help you read it through.
Craigslist is a great place to start. Make certain that there is a clause protecting you should they default. If they are foreclosed on because of mismanagement there is virtually nothing but civil court to protect your non-excercised interest in the property.
Could be a win-win if both parties do their part. I have sold my last 2 homes this way.