Another Critter Looking to Make a Fall Move: Ants
Typically, ants are attracted to a variety of food types including carbohydrates (sugars), proteins (meats), fats and oils but cooler weather can make them particularly active.. Colonies, or "nests", are located in protected places in walls, under floors, under cabinets, and such and individual colonies can be quite large with thousands of ants.
Your first step should be sanitation. Clean up crumbs, cooking oil, and all sources of water. This alone will go a long way toward reducing ant problems by depriving foraging ants of food and water. Also, patch holes around pipes and wires that pass into the living space. Ants use these "highways" to gain entry from colonies located in walls, the crawlspace, and so forth.
Baits work much better than conventional insecticides because of the unique way worker ants feed the colony, including the queen. K&B True Value carries many varieties of baits/traps and conventional sprays.