Perhaps you could try running an ad on Craigslist saying what you’re looking for and how much you’re willing to spend? See what kind of responses you get. No reason to be passive here when the data is so important to your analysis. Search for other ways as well, like property management companies, etc….
I think you may discover an interesting trend as well as pick-up some data that’s not easily attainable. I’ve often wanted to see a correlation of rental prices for a given unemployment level. Or occupancy rates of residential units and homes correlated to rental price trends. A study well worth making these days since so many are utilizing the “rent vs. buy” calculation as their logic for purchasing right now.