Jungle Java Cafe is the most popular coffee shop in Guam. It is located in the heart of Tumon which is the tourist section of the island. There are no links here to this wonderful shop, or the coffee they roast and sell but you may be interested in some of these sites:
The Coffee Gourmet- Great selection of coffees at terrific prices.
The Coffee Yellow Pages- An extensive list of Hawaiian coffee producers, roasters, shops, etc.