Another Brit here! waves I've been eating Paleo for three months now. :)
I buy grass fed meat and free range eggs from Piper's Farm butcher, fresh fish from the fishmonger on my road and organic veg generally from my local Waitrose. Also get items like organic coconut oil and coconut milk from either Waitrose or local health food store.
My favourite cheat is coconut oil mixed with Green and Black's cocoa powder and a teensy dribble of raw honey. It's beyond good.
I tend to stick to 'meat and two veg' type meals--also make a lot of curries and chillis which I serve with cauliflower "rice".
Basically I now use courgette and cauliflower wherever I would have used pasta or rice (either sliced for 'lasagna' or in ribbons for 'spaghetti' - I've also used sweet potato as 'spaghetti' too) and cauliflower blitzed in a food processor in place of rice.
Kale chips make a surprisingly good snack.
Organic chicken livers fried in lard with onions and then blended smooth into pate is gorgeous eaten as a dip on veg sicks.
Any time I need something cheat-ish I use coconut flour, coconut oil and a bit of honey / lemon zest / vanilla essence blitzed in a food processor, smooshed into cookies and baked for about 10 minutes at 170 degrees C. ;)