We use the Sweetleaf brand stevia as well. It's nothing but stevia and a tiny amount goes a LONG way. I put 1/8 of a tsp in my husband's coffee and he likens it to 2 tsp of sugar in terms of sweetness.

I agree with weaning yourself off sugar all together though. I did it when I graduated from college because I just didn't want the hassle of sugar in my coffee. Now I can't stand sweet coffee, so it's possible. Start by reducing the amount a little by little. I'd bet that in a month, you could totally adjust to sugar free without too much pain.