Within the standard Abilene outfitter's store, Valencia would find the proprietor to be a half-elven woman like herself, though rather than being of the high-elf breed it seemed she was half-wood elf instead.  Wearing a suit of platemail that did<em>everything</em>to accentuate her curves by some miracle of blacksmithing, she would explain that if you were looking for poisons, they had a number of poisons, the most frequently sold and affordable being Bloodroot and Black adder venom, both capable of tearing down a mark's immune system and bodily organs over time, but they weren't instant and they wouldn't be taking down a well trained and battle-hardened warrior, though a mage or aristocrat likely stood little chance.  However, all of their poisons were under two-hundred gold pieces; clearly on the lower end of the cost spectrum.<br/><br/>In the poison-crafter's establishment, the place would look remarkably like an alchemist's shop, save for with a slightly different smell to it.  The proprieter was a drow, clad in nothing but a smile and a pair of slippers, who when you enter is currently being serviced orally by another customer, a dwarven lass who is on her knees before the woman, eating her out and, judging by the moaning from the drow, doing a really damn good job at it.  Even while being serviced so, she explains that there isn't a poison she hasn't heard or made, nor that she doesn't have on hand either.  Her specialty is naturally the infamous Drow poison, but she carries things as rare as Dragon Bile and as common as basic as arsenic.  Her recommendation is Nitharit, a contact poison running about six-hundred and fifty gold a dose, and while it's not the fastest poison it<em>is</em>one of the more potent for it's speed and is more than capable of taking out a mark if he manages to get away.<br/><br/>Naturally, if you had a preference for the drow woman that was... perhaps a bit outside the given price-range, she was always open to offers of...<em>alternate</em>payments to help reduce the price, such as what the dwarven woman had<em>just</em>finished doing for her.<br/><br/>Luckily, there is a list of poisons under the Afflictions section of the Pathfinder SRD link I gave you, if you'd like to look some up.  I have the list though, so if you don't want to that's perfectly fine.