If you need to keep ground coffee for a long time, will keeping it in the freezer help?
Yes, buying fresh coffee is better and grinding right before using is optimal. I think we mostly agree on that. That said, it IS possible to freeze coffee without completely destroying it. There are a number of variables that you want to account for. Here is a short summary:


It should sealed very tightly, a mason jar would work well for example. Even better is to freeze the unopened bag (with the valve taped shut), but that defeats your goal I think of consuming slowly.
If at all possible, put into the freezer once, remove once. NO refreezing. Taking the whole batch  in and out of the freezer every time you use it could cause condensation which will damage your beans.
Freeze the coffee whole. Grind right before use.
Take the coffee out of the bag, let it come to room temperature before grinding it.
Once it comes out of the freezer, it's back to being optimally consumed in a couple weeks.


There is a limit to how long you can freeze it. I wouldn't leave it more than a few months? Here's a good, but long read on the subject, including some taste test results. If you're really seriously interested, I'd give that a good read.

If you're not a big coffee drinker, and your guests aren't picky either, you might not care about all those variables. I'd do some testing to see what works for you (don't test with the expensive stuff of course...). If you and your guests can't taste the difference, the extra precautions are kind of for naught. I have certain family members who claim to prefer the crappy, flavourless stuff for example. :-P sigh

Last note. Never store coffee in the fridge. Why not? Quoted from here:


  "The Starbucks web site says: "Think of coffee as fresh produce. The enemies of coffee are oxygen, light, heat, and moisture. To keep coffee fresh, store it in an opaque, airtight container at room temperature. Storing coffee in the refrigerator or freezer for daily use can damage the coffee as warm, moist air condenses to the beans whenever the container is opened."