actually any liquid is considered a potion [directed at post number 3, not you zaza1]
i'm a potion user also, and i have two books that are very good in my opinion
~Magick Potions: how to prepare and use homemade oils, aphrodisiacs, brews and much more by Gerina Dunwich
~Oils, Incense and Brews by Scott Cunningham
the first one is more historical, the second one is more making and using. it's rather hard to find, in my opinion, books on the subject. potions work better for me as well, but i believe its because since i'm using herbs, i know they have healing [or whatever] properties, so they will work. let me know if you would like any help.