Craigslist works the best, followed by Hotpads.com for finding rentals.

I have always gotten the best deals with craigslist posts that have no pictures. It shows the landlord is lazy and just wants it rented, in my opinion.

But craigslist can be a pain, because it is so hard to find where the place is. On Hotpads.com you can just look at the listings on the map. But, they are put up by management companies, and therefore are working harder to get a premium for the place.