Scott says that digital signal processing is at the heart of a soundbar, and they are great for small living rooms. Atmos is now making its way into soundbars and it's the least expensive way to significantly improve your sound, especially if your soundbar comes with a subwoofer. Leo says that there's a wide range of prices for soundbars, though, and Scott agrees. You get what you pay for. But there are some good budget brands out there including Vizio (of course) and Polk.
The Polk Magnify Mini is $250 and it comes with a wireless subwoofer. Vizio makes different sizes depending on your TV size. They make a 2.0, 2.1 (with subwoofer) and even a 5.1 soundbar with satellite speakers for surround sound. The Yamaha YAS-207 for $300 is a good soundbar as well.
The next level is the Samsung HW-MS650 for $450. There's also the Samsung HW-MS750 with wireless subwoofer for $1200. Then at the top of the list, there's the Sony HT-ST5000 for $1500. This gives you Atmos surround sound from the bar itself.