I'm not nearly the cook that some of the mamas on this board are, but I do have one piece of advice. It might be the kind of tomatoes you used last year that made your sauce runny. You might try Roma tomatoes this year. Romas are known for being more "solid"/less liquidy and are often used for making sauces.
Another option would be to chop up your tomatoes and then to let them "drain" a bit by placing them in a strainer over a bowl.
If you have a garden, I don't think it would be too late to add a roma tomato plant to your garden. You'd probably have to buy a start at the nursery. Most romas (and other sauce-type tomatoes) will produce a bunch of tomatoes all at once. (There is a name for this type of tomato plant that I can't remember. Determinate/indeterminate???) It is different from the typical garden tomato plant because it produces a whole bunch of fruit all at once instead of continual fruiting over a couple of months. This makes it a great plant if you plan to do a lot of sauce making.