A lot of people make peach salsa without cooking it down. I'm sure that's delicious but I love the texture of cooked peaches, so I chose to cook mine down. Here is what I used to make this amazing condiment (it's so good I want to eat it like it's the main course!):
6-8 small peaches (they were very small - but oh so delicious - picked from a friends tree), diced
1 med/lrg garden fresh tomato
My peaches were sweet enough and bursting with flavor, so I didn't add any sweetener. You might want to if your peaches aren't as ripe as mine were (mine were actually over-ripe). Nothing is as good as sweet and spicy! I also left the peach skins on, but that's optional. I put the cut peaches in my saucepan and added around 3/4 cup water and let them simmer until soft and easy to mash. As they cooked I sliced up my jalapeno pepper (I only had one since I used all the others for dinner last night but if you are buying yours from the store or have more in your garden than I did, use them! They're delicious with the sweet peaches), tomato (again, I only had one from the garden today), and some cilantro. All of this is just to taste, so keep tasting as you make this salsa and add stuff until it tastes how you want! After I slightly mashed the peaches I added the pepper, tomato, and a pinch of salt and a LOT of cayenne (I wanted it speecy spicy), and let it simmer for just a couple more minutes. Took it off the heat, added a little more cilantro, and let it sit to cool. Now I just have practice great self-control as I wait for dinner to be ready before I can devour it.