To make your own:
Put together in a pan: Juice from a 4 oz can of pineapple chunks or rings, ¼ cup of tomato ketchup, ¼ cup of distilled white vinegar, ¼ cup of brown sugar and 1½ tbsp of cornflower. Mix well and heat until the mixture thickens. Job done.
Yes I do and am a competent cook but my children like the sauce which comes from our takeaway and wondered if anyone would be able to help - obviously not!
Your local Chinese takeaway will probably sell this on it's own as an 'extra/side dish'.
Sweet 'N' Sour sauce is readily available at your local Supermarket (UK).
Not that I'm advertising or promoting them but Blue Dragon and Uncle Ben's do good sauces.
Was at my daughters the other night and for a recipe she needed plum sauce. In less than the time it would have taken me to walk to shop to look for this she found a recipe on Internet and made some with a punnet of reduced price plums she had. Delicious!
I can't really see what the difficulty is. Sweet and Sour Sauce is available just about anywhere. Most places have a Chinese and/or Indian foodshop nearby. This is where restaurants and takeaways get their sauce from.
But Graham-W's recipe looks nice ! I remember making something similar years ago and it was very tasty.