Dunno about the invis thing, but the only only ONLY place thistle tea comes from is a rogue quest. once per rogue. thats it. If you want it, start a rogue, get to that quest, beat it, send it to yerself, and delete the char. Or hope someone doesn't want it. Check the AH? Dunno.
Yours,
Khay
-P.S.- NVM. I just found out that they DID add the ability to buy it in the new patch. My mistake. How Stupid.
Edited, Tue Mar 22 22:16:23 2005 by KhayPrower