Any tips bees can share with me on a searching for a rental house?

We are getting ready to move next month to a town a few hours away. I've been checking Trulia, Zillow and Realtor sites every day and inquiring about rentals, but it's been frustrating so far. Seems like rental agents are not very responsive! I'm worried we'll have to jump on a rental site unseen in order to not lose out. We're limited to only being able to visit on weekends, if needed.