Take the frozen berries, place it in a pan, and add just a bit of water to it. Bring to a boil. Taste, and add sugar and lemon juice to taste. Add water or reduce to get the consistency that you like.
Fresh stone fruit, like apples, pears, peaches, etc., you can just slice, and saute in a bit of butter. If you have some fruit juice or nectar (look for little cans either in the International aisle at the grocery store, or with the rest of the juices), deglaze the pan with that, then cook down.
I can't really give you quantities, as this, for me at least, is a "cook by the seat of your pants" type thing.
Personally, I feel that dehydrated fruit makes a better sauce for this. For dehydrated fruit, I would just place the fruit in a small saucepan, cover with the appropriate fruit juice, and simmer until hydrated. Add sugar and lemon juice to taste.
Peace, Love, and Vegetable Rights!
Eat Meat and Save the Plants!