I have been using stevia to sweeten liquids for several years; I buy mine at the health food store or from http://www.stevia.com/ (the website has information on the different formulations of stevia).
Rosa, I just bought stevia packets with FOS but haven't tried them yet. I need to start carrying the packets with me to avoid artificial sweeteners when I'm away from home... I used SweetNLow in tea at work on Thursday when I forgot my stevia bottle and noticed I was much hungrier and had food cravings all day, which hadn't been happening when I consumed no artificial sweeteners. (Yes, I do still drink tea, although I've cut down... hard to imagine cutting it out altogether).
Judy, I think my sister might have made cheesecake with stevia, I'll have to ask her about it.
Wren