Supermarkets
The closet supermarket to Spinnakers is Sainsburys (map). It is within fairly easy walking. Walk towards Newquay until you reach the golf club. Keep the golf course on your left until the far end, then turn left, still keeping the golf course on your left until you reach Hope Road turning on the right. If you get to the golf club house (looks like a little castle) you have gone too far.
You can walk to Sainsburys by taking the path around the back on Fistral beach and then following the public footpath across the golf course. This will bring you to a small car park. Turn right in to Tower Road and then left into Sydney Road. You will see the Sainsburys car park on your right.
There is a large Morrisons out of town (map). You should get all you need here, it has good parking and a fuel station. It can get VERY busy in the season.
Others include Aldi on Cliff Road, Lidl on Treloggan Road, Two Tesco Express on East Street and Hillgrove Road
Butchers
Chester Road Butchers or Kitchen and Co Butchers as they are actually called (map) are pretty good. Have a look at their Tripadvisor page.
Baker
There are a number of bakers through the town. One is Pavilion Bakery on Fore Street (map). Another on the way out of town is Malcolm Barnecutt's on Henver Road (map). We often get pasties here, they are nearly always very fresh.
Petrol Station
The nearest is on Trevemper Road. But just a little further is the petrol station at Morrison's supermarket
Post Office (main street)
Wine merchant / off license
Obviously, there are the supermarkets, Sainsbury's, Morrison's
If you are travelling, there is a very good wine merchant in Wadebridge, called Wadebridge Wines
Farm shop
There is a great farm shop - Trevilly Farm shop (https://www.trevilleyfarm.com/)