Hi there, as far as I can tell at this time, and I will update this page with how many vendors are missing but surely the West Karana vendor (Gindlin Toxfodder -3000, -13400, in a hut at the houses) and Lesser Faydark vendor (Anelia Thrywiel -150, 1200, Woodelf encampment) are classic. there is lore from qeynos that shows you have to go to toxfodder for the spine break in the book " Renux's Translation" from Pelshia Thuxpire in North Queynos Rogues Guild (50/280).
I use the old school rogue page Kiky's poisonous pages at
http://kikyara.tripod.com/
Keep in mind that these vendors were available before the last patch, someone screwed us rogues