ISO: making salsa, using canned tomatoes, to can

My husband and I are new to canning. We have a variety of hot peppers in our garden that we want to make salsa with. We are using already canned tomatoes in our salsa recipies and just want to make sure if we use these tomatoes, with a little bit of lime juice added, presents a danger of too low of an acidity level. Our question is, does anyone have any experience with canning salsa with already canned (like Hunts or Kuners) tomatoes, that may or may not have citric acid already added to them?