Thats a shame moorej, if you'd kept some of the branches you might have been able to strike some cuttings, but the chances of getting any stump shoots to develop into anything worth retaining are very slim, you're much more likely to end up with something looking very much like a coppice;
my advice is to remove the stump (have it ground out) and start again. maybe this time have an area in the lawn with turf removed dedicated to the growth of the tree, as much space as you can, well mulched 2-3inches thick not touching the stem of the new sapling.