When you are picky about the coffee that you drink (and if you are perfectly fine to have no coffee over coffee that tastes bad) you quickly learn that the quality and type of coffee beans you use are key. I have never been able to drink coffee that comes from a can that is pre-ground. I have learned that coffee starts to become stale with seconds of its grinding, and I am very sensitive to that. So I have always sought out whole beans and ground them myself. I'm not going to talk about grinders in this post; that is for another day.
Grocery stores now like to carry large selections of whole coffee beans, most of while sells very slowly. Coffee beans used in drip makers need to be used within 2 weeks of roasting before they become stale and the oils start to become rancid.
With this background starts my journey. For a while I got coffee beans at Starbucks, but the quality and age of the beans was too inconsistent, other than their Black Apron high end line, which is delivered to most of their stores around the first of the month in limited quantities and is excellent, and is unbelievable expensive at about $25 a pound.
For a long time, my mother-in-law sent us freshly roasted coffee from a Costco located in Brentwood, Tennessee, where green coffee beans are roasted daily, and often the coffee you buy is in a warm bag. That worked very well. Until we decided to go espresso.
Espresso coffee is not from a dark roasted coffee--its usually from a medium roast. A dark roast tastes burned after it runs through the heat and pressure of an espresso machine. Also, expresso roast coffee has a much narrower window of freshness because the concentration of the flavors of the coffee will bring out the flaws.
Good espresso cannot be bought at grocery stores. Julia's Coffee, a coffee shop with fair competent baristas, will sell you some of their coffee out of their stock if you ask nice. Dilworth Coffee, a local roaster with franchised stores, has very inconsistent quality and packages coffee poorly. You want to buy your coffee in sealed packages that have a little breathing valve on it so that gases can escape the coffee but oxygen cannot get in. You never want to buy coffee from an open bin. Also never buy coffee that is already flavored--the flavoring for these coffees is mixed with egg white and sprayed on the coffee beans. Yech. Use a syrup.
Currently I am splitting my orders between a very competent roaster from Raleigh, Counter Culture Coffee, and Intelligentsia Coffee in Chicago, which is reputed to have the best espresso blend you can buy, Black Cat.