I've started blending my own tea with inexpensive herbs from the health food store and a little advice from Rosemary Gladstar's Family Herbal book. My local store has a great bulk herb section, but I still haven't been able to find all the varieties I want to try. I found seeds for a few of them and started a small container garden just for tea herbs.
Here is a blend that I like particularly well, I've been calling it "Daily Boost" :
Mix equal parts