I used these on a deck thats just about 2 feet above ground:
http://www.deckplans.com/
They are concrete blocks that you slot 4x4's into to create the supports for the deck. The idea is that you don't worry about frost lines and heave, because the deck floats on the surface. You don't worry about the deck sinking, because you use enough of the blocks that the weight distribution is very low.
After two years, there is no discernable change in the gap between the deck and the house, and the deck hasn't settled or shifted at all.
Awesome product, imho.
-Scott