Mathematica, 2746 characters
Outer[List,d=Range[-1,1],d]
Here is a different (straight-forward) approach using 30 characters:
Range[{i,j},{i,-1,1},d]~Flatten~1~Drop~{j,-1,15}]
Note that these produce nested lists (basically a matrix where each element is equal to its coordinates)Well. If you don't want that you need to surround each answer in Flatten[...,1]
for another 11 charactersGenerates all 9 coordinates, flattens the list and drops the centre.