I used the scone recipe from here, but the scones turned out really hard and dry. What should I have done differently? More butter, more milk. Less cooking time?  http://www.taste.com.au/recipes/8163/basic+scones 
The proportions on everything look correct (including the milk!) EXCEPT that is a very small amount of butter for 3C flour.  There is also no sugar in that recipe--and even a very small amount of sugar will change the texture of the dough.  I personally would triple the amount of butter, add 2-3T sugar, and then re-try the recipe.  VERY cold butter will also help with a lighter finished baked scone.  As for the comment that the oven time is too hot and long---the temperature is good--but I would think the baking time would fall more in the range of 15-20 minutes, depending upon whether you are baking from frozen dough or freshly made scone dough.  A hot oven, as opposed to a moderate oven (350 degrees F--normal for cookies and cakes) is recommended for biscuits and scones.  Since all ovens bake differently, rely less on the actual time and more on how the scone looks--it should be lightly golden on top and not doughy in appearance in the center.  A cake tester can be used to be certain that the center is fully baked.  good luck--it always seems to take a little effort to find the scone recipe that you think is perfect!! 