Several stones to hunt out there (and a bit closer than Alphamstone, which is admittedly more spectacular than the puddingstones) - details of the Puddingstone Trail can be found on the Meg Portal.
Moss writes about Great Canfield church on her blog by the way - http://northstoke.blogspot.com/2009/05/great-canfield-church.html and as both Avebury and Essex have been mentioned here, this bit especially may be of interest -
"Right hand pillar of the tymphaneum with Odin and serpents? It has the 'dot' all down the serpent back, as seen on the Avebury font serpents. The tails are fanned out similar to a fish tail. 'The legend goes that the world serpent with his tail in his mouth was doomed to lie in the ocean encircling the world till the Ragnarok. Should the tail ever be pulled out of the jaws, universal calamity would follow.' Brian Branston - The Lost Gods of England."