When you've had a few sessions in Sainsburys, try Silverdale.....won't be so much a case of practicing how to park, more a case of practicing how to find a parking space, and how to waste time driving around The Thorpes killing 5 mins hoping that someone has moved by the time you pass by again.....
Also good for practicing controlling your road rage when someone moves out of a space, and you and fifteen other vehicles all try to fill it at the same time....