You might also try contacting some real estate companies directly whom manage properties.. I know we currently don't have any available in Midlant, TX. but we do get some from time to time. As you might have already found out the market is really tight for rentals but be persistent and you'll find something.
Oh and don't forget about the good old way of finding something... the newspaper.. although you can now search their site online.
Check out rent.com, realtor.com, and craigslist.com. Thatâ€™s where youâ€™ll find the most rental listings. You might also check with one of the property managers in your local area to see what they have or will have in the near future.