If you are ordering the house sake at restaurants in the US, then the odds are very good you are drinking Gekkeikan Traditional Sake http://www.gekkeikan-sake.com/pr..., which is made in Folsom, CA. Any decent sized wine and spirits retailer should carry it. It is also possible you are drinking the basic brews of Ozeki, Sho Chiku Bai or Hakutsuru. Thes... (more) There are many ways to heat sake, but the most common method is to purchase a ceramic sake set http://www.amazon.com/s/ref=nb_s..., bring a pot of water to boil on the stove and set your tokkuri (ceramic bottle) in the boiling water for a few minutes until the desired temperature is reached.
Keep in mind that not all higher grade sakes will taste good wa... (more)
Style of sake is largely up to the brewer. But broadly speaking the sakes of the northeast tend to be lighter and drier, while sake from the southwest is more full-bodied with noticeable sweetness.