You can typically find nicotine sulfate, which is a common form of nicotine used in agriculture as a pesticide, at stores that specialize in agricultural supplies or online retailers that sell agricultural chemicals. However, it's important to note that the sale and use of nicotine sulfate may be regulated in your area, and it can be toxic if not handled properly. Be sure to follow all safety precautions and local regulations when purchasing and using nicotine sulfate. Usually found in establishments that specialize in agricultural goods or online sellers who sell agricultural chemicals, nicotine sulfate is a common type of nicotine used as a pesticide in agriculture. It's crucial to remember that nicotine sulfate can be poisonous if not used correctly and that its use and sale may be regulated in your community. When buying and using nicotine sulfate, make sure to abide by all local laws and safety precautions.