Spaghetti sauce is the first thing I learned to make as a kid. You add oregano, basil, and parsley (dried) to tomato sauce, sometimes beginning with garlic and onion in a little olive oil, sometimes adding garlic and onion powder. Sometimes you even dropped meatballs into the bubbling concoction.
A little more money, and you can buy Classico. The reasons I recommend Classico: Everything else in its price range contains sugar. We love Classico Spicy Red Pepper (a.k.a. Arrabbiata).
Last week we discovered Culinary Circle, which is a lot more money, but what a sauce! Puttanesca and Arrabbiata to start, plus the Spicy Italian Sausage. These feature wine where other sauces use sugar or--horrors--corn syrup. Classico and Culinary Circle: spaghetti sauces worth picking up.