Look for an all natural brand which has not been cut with other sweeteners. One of the most common mistakes people make when using stevia is adding too much. For a cup of tea a light dusting will do. Stevia does not taste like sugar, it is just super sweet - up to 30 times as sweet. It works well in baked recipes. For example, if a batch of cookies calls for 1 cup of sugar, reduce the sugar in half and add about 1/4 tsp. of powdered stevia extract with little or no compromise in sweetness.
Lemonade? Sweeten it with stevia instead of sugar.