Try walking the coast from Crantock to Holywell Bay - massive dunes here and in between the lovely Porth Joke.
Caroline
I stayed 2 years ago at an apartment right opposite Whipsiderry beach on the road heading north out of Newquay, 5 mins from town centre and is a secluded bay with a fabulous view of the sunset. Quite a few steep steps down to the shore though
http://farm4.static.flickr.com/3350/3535426865_9ec39e4b13_o.jpg
edit: actually, the full flickr set, most have got locations in the description and I managed to find those places with only 4 days there. http://www.flickr.com/photos/wgi/sets/72157618170350151/