Sound bar? The 5.1 RCA receivers they sell at Wal-Mart for <$150 are great for movies, especially for the price. I don’t really recommend them for music but they are fantastic for movies. They can do dolby surround (matrix), dolby digital, and dts.
The only 5.1 speakers sets I see at walmart come with a BD player, and are about $300. Canadian dollars, mind, but still high enough that my bank declined the card when I tried to get it last time I was in the city.
I would assume that the guy at a specialist shop for sound systems (and some guitars, but mostly home sound systems) would be a decent first step for research. He might aim to deceive, but I suspect a small business in a small town would consider that risky at best.