Found this by chance yesterday -
http://oisat.org/; the biggest library of witches' brews and wizards' potions I've seen.
Some are truly foul sounding - and I feel a bit uneasy that there's lots of recipes but little information on how effective they might be? Not that I would dream of suggesting that any of them should be used, of course ;).
How long are your arms? ;)
All best - Gavin