Absinthe (thujone) is terrible. Stick to shamanism!
http://peyoteway.org/spiritwalk.php$300, March-September is available. It would probably cost me $1000 for a trip like that (round trip ticket + weeks worth of food + admission fee). Damn. That will be a while, but I don't actually mind waiting. I think of it like the time between salvia trips. The only reason I don't go looking for this stuff on the street and doing it in wilderness that I am familiar with is because it's so rare! No one synthesizes mescaline or psilocybin anymore. Home grown peyote is way more respectful, too. Guaranteed to give a pure experience (in the back of my mind I wouldn't be thinking about impurities or something).
Like I was trying to say, dietary purification is part of shamanic practices. It is so that the other chemicals don't alter the experience. Addiction withdrawals are entirely different, but yeah, if you're a smoker and a psychonaut I can't even imagine what terrible trips you've had.
I'm much younger than you advertised yourself to be, but it would be really damn cool to drive down, pick you up, meet a bunch of other random guys, head to Arizona, have our spirit walk (individually), rest up, blow each others' minds, and drive back. If I did end up doing this trip, I'd find one or more of you on here to do salvia with as well. It would be beautiful.