I order my coffee from George Howell at terroircoffee.com. George is one of the pioneers in the specialty coffee
George is one of the giants of Specialty Coffee in North America, and buys, roasts and provides some fantastic coffees. Some of his roasts are on the very mild side, so this should be considered. Here is a list of some fantastic roasters and purveyors of specialty coffees in the USA to compliment the list of Canadian roasters provided above:
Heart Coffee Roasters, Portland - http://www.heartroasters.com/collections/all
Stumptown Coffee, Portland - http://buy.stumptowncoffee.com/
PT's Coffee, Topeka - http://store.ptscoffee.com/coffees/
Mad Cap Coffee, Grand Rapids - https://madcapcoffee.com/buy/
Intelligentsia Coffee, Chicago/LA - http://www.intelligentsiacoffee.com/
Ritual Coffee Roasters, San Francisco - http://www.ritualroasters.com/coffee-club/
Oren's Daily Roast, NYC - https://www.orensdailyroast.com/#
Batdorf & Bronson, Atlanta - http://www.batdorfcoffee.com/index.php/all-coffees/
Counter Culture Coffee, Durham - http://counterculturecoffee.com/store/coffee
Terroir Coffee/George Howell Coffee, Boston - http://store.georgehowellcoffee.com/coffees/
Verve Coffee Roasters, Santa Cruz - http://www.vervecoffeeroasters.com/collections/coffee
Handsome Coffee Roasters, LA - http://www.handsomecoffee.com/coffee.html
That ought to get you started, with a who's who of some of the best micro-roasters in the USA.
Enjoy!
-- Pat