Doris,
I have found the KEY to sweet and sour sauce is using Rice Vinegar which is
available in the ethnic foods section of many grocery stores. If you can't
find it there ask someone near a China Town to pick some up for you as it is
readily available in Asian markets.
Here is my Red Sweet and Sour Sauce
1 c. water
1/2 c. sugar
1/4 c. rice vinegar
1 t. salt
2 T cornstarch
4 T. water
1 T. red food coloring
Boil first amount of water then lower heat and add sugar, vinegar and salt.
Mix cornstarch water and coloring. Gradually add to hot mixture stirring
constantly until thickened.

I especially like to vary this one for a spicy sweet and sour chicken served
over rice. Add Chinese chili garlic sauce to taste (I use 2 T.) which is also
readily avaible at Asian markets. Or you can add crushed red chili peppers (1
tsp). Hope this recipe helps you find what you are looking for.
If you like spicy sweet and sour dishes be sure and try the crispy fried beef
recipe posted here in the kitchen link. It is just like the restaurants Ginger
fried Beef!!! ---Jen