Hi Angel Eyes,
Pure essential oil from the Tea Tree plant (Melaleuca Alternifolia) can be bought at Boots, Holland & Barrett, any Health Food shop and most 'New Age' type shops.
Usually the higher the price the better the oils BUT economically you find one you like and can afford and go with that.
I've tried Tea Tree oil, Lavender Oil on my warts/verucae all to no avail and yet, when I recommend these remedies to others, their's vanish with amazing rapidity. Perhaps I'm a wart charmer and my burden is to carry the warts of others[].
I'm off to raid the garlic jar - anyone for smelly feet?????