Cookbooks appear based on how fat you are and how many ingredients you purchase. If you go through the whole game only buying the 'necessary' ingredients then the intermediate and advanced cookbooks will likely never show up. I'd recommend attempting to buy 5-10 of all ingredients per visit until they show up on the NEXT visit. Fat size also matters, the intermediate cookbook only became available for me (after buying a ridiculous amount of ingredients) after Aubrey had surpassed 200+ pounds.