I love making spaghetti sauce with fresh tomatoes & fresh herbs! I wash & core the tomatoes & then throw them in a blender - seeds, skin & all. I cook them down to the consistency I want/like. At this point, I sometimes freeze containers of the tomotoes for future use.
For sauce, I add a can of tomato paste & herbs & spices like fresh garlic, basil, oregano. I also add a pinch of baking soda to cut the acid especially in fresh tomotoes & a pinch of either sugar or cinnamon. Enjoy your fresh tomatoes!