I have been making homemade salsa forever - everyone has their own recipe - I have several, but this one is the easiest one to make. Just the basics:

6 medium vine ripened tomatoes, blanched to remove skins, roughly chopped
1/2 vidalia or red onion, coarsely chopped
1 jalapeno pepper, roasted and finely minced with seeds
3 cloves garlic, roasted and minced
1/3 C fresh cilantro, roughly chopped
2 tbsp. extra virgin olive oil
2 tbsp. lime juice
1 tbsp. red wine vinegar
pinch of coarse salt
pinch of cracked pepper

In a food processor or a blender, combine all ingredients and "pulse" or lightly blend. Chill overnight and serve with tortilla chips.