I have kefir grains and would be happy to share them. Just send me a PM and I will send you grains so you can make your own real kefir.

I don't know for sure about the carbs but I kind of believe the little buggies eat the sugar and if it's nice and sour it shouldn't be too bad carbwise. You could also make it with half and half to lower the carbs a bit if you aren't afraid of fat or calories.

You can strain it like you do with yogurt to make a "cheese" if you want something more solid than the usual creamy drinkable texture. I love the stuff! (And I agree, the stuff you get in the store isn't real kefir; it's more like thin yogurt. The real stuff is miles better!)