Williamson County Apartments For Rent . Browse williamson county, tx real estate. Find 3106 homes for sale in williamson county with a median listing home price of $495,000. Great Hills Apartments Austin, TX from www.apartments.com Search 75,438 apartments for rent and mls listings. View listing photos and nearby sales, and find the perfect apartments for rent. Find 991 homes for sale in williamson county with a median listing home price of $850,000.