If you buy coffee at a grocery store, your options are somewhat limited. There are only so many times you can stare down the same  grocery store  shelf before you start wondering if there's something better you've been overlooking. So I went looking -- working through nearly a dozen options across national chains and local shops, from the classics everyone defaults to and the newcomers trying to earn a spot in your rotation.  There's Good (and Very Bad) Coffee at the Grocery Store. I Tested 20 Bags to Find the Best Five best grocery store coffees Café Bustelo Espresso Ground Coffee Stumptown Holler Mountain organic blend Whole Foods Market Organic Early Bird Blend Dunkin Original Blend Illy Classico Honorable mention 5 grocery store coffees to avoid You don't have to spend $20 a bag for good coffee. Here are the best beans you'll find at the supermarket.…