Because Murfreesboro and Smyrna aren't any option, you may want to look at La Vergne (Rutherford County) and Nolensville (Williamson County). I'm not too familiar with La Vergne, but Nolensville is a great little town. It has a small town center and has a lot of farms and land, but is growing a lot, too. As far as your price range, I know of two subdivisions in Nolensville building homes from the $300's: Bent Creek and Silver Stream, so you may want to Google those if you're interested.
Both Rutherford and Williamson Counties are great places to live. Williamson County Schools were ranked as the top public school system in TN in 2006, but Rutherford County also has very good schools. Rutherford County is more industrial and working class, while Williamson County is known of being more white collar and last year was ranked as the 11th wealthiest county in the U.S. For example, Smyrna (Rutherford) is home to a big Nissan manufacturing plant, while Franklin (Williamson) is now home to the Nissan Nat'l Headquarters. However, Williamson County does have some blue collar areas, as Rutherford County does have some upper class areas.
Good luck with your decision and merry Christmas!
