Beef short ribs have a small section of bone with a large chunk of meat on them. They can be found at Korean grocery stores and many other butchers.
My cookbooks
Which to get? my first book has all the recipes for all the essential Korean pastes and sauces, but my second book Maangchi's Big Book of Korean Cooking has more recipes. Both are best sellers and either one is a good choice if you want to learn Korean home cooking.