If you're looking to buy coffee beans and you care a lot about the quality of the coffee, I can tell you what I've learned about selecting beans. There's this really good cafe near where I live that serves
really good coffee for just under what Starbucks charges, and the owner is friendly and really knows his stuff. So I got around to talking to him and he told me that if you want high quality beans, the most important information is the roast date. If a place can't tell you the roast date, don't expect anything special. You want coffee that's within 14 days of its roast date for the best beans possible.
The next thing to look for is oil. Shiny beans are a sign of over-roasting. Those oils should be contained within the bean, and only come out if they've been roasted too long or too hot. The oils go "putrid," as he described it, within a day or so of being exposed to air, attributing to that overly sour/bitter taste of some coffee. This is the same reason coffee snobs frown upon buying ground coffee; the oils become exposed to the air and the coffee becomes stale quickly. So, don't buy shiny beans or beans that come from a container that have oil along the walls. And then it's advisable to store the beans in an airtight container when you get them home. I've kept beans this way for around 30 days without a problem.
Finally, black beans are generally a sign of over-roasting as well. They shouldn't be more than a dark brown, but not black or almost black.
I've been following these guidelines for a while now and have been waking up to amazing coffee in the morning. I buy locally, though, not online. You will pay a higher price for higher quality beans... but if you're particular about taste, it'll be more than worth it, and still way cheaper than going out for coffee every day. You'll probably be able to find some small, local cafes near your area on Yelp which will carry good beans if you're willing to buy locally.
Of course, if you're not super picky, there's no sense in worrying about any of this stuff.
