DQ, try getting whole potatos (yukon golds or red skinned work the best) and nuke them in the microwave for about 6 minutes or until they're done depending on you microwave. They seem to stay solid but cooked.
I make my own potato salad sauce which is a mixture of mustard, mayo, sugar, and vinegar. I don't have a recipe but usually just make it until it's mildly sweet and soul and slightly thinner than mayo. Then I finely chop some onion. celery, and green pepper. Then mix it all up with the potatos.