For years I thought that if I kept my fresh roasted/ground coffee in the freezer, it would keep it fresh. I could not have been more incorrect.
Contrary to popular belief, it is probably one of the worse places. Freezing or refrigerated grounds or beans will dry out and rob the natural moisture from the product quicker than if you simply put it in a sealed container and left it on the counter. This is expecially true for gound coffee.
Really, the best method is to keep all grounds or fresh roasted beans in an air tight container or a bag that has been vacuumed sealed. Place all unused coffee grounds or beans in an area that is cool and dark. You may also want to consider buying in a smaller package. Reasoning behind this is the fact it will get used quicker leaving little time for loss of quality.