Been canning for 35+ years now. It is not all that much work.
Do not use a water bath method. That has so many more pitfalls than pressure canning.
Our pressure canner holds 5-6 quarts. It is old, leaks water around the seal a bit, so we compensate by canning 5-15 minutes longer depending on what it is. Always longer if meat is involved.
Anyway, for fresh tomatoes. Just blanch them for 2-3 minutes in boiling water, scoop them out, put into a food mill. There are all kinds. We use one that you crank, and the juice/puree comes out on the left hand side, and the skin and seeds come out in front. We dump the skin and seeds back in and crank again, maybe 3 times.
My wife puts the jars through the dishwasher to make sure they're clean. We use our finger to rub the entire circular surface of the jar to feel for any cracks/divits.
You boil your lids in water for 10 minutes (or was it 5 minutes) I forget, because that part the wife does.
You fill the jars to the point where the jar starts to narrow, no further. That's why the jars are shaped the way they are! Pretty cool, huh?!~
Then you wipe off the top of the jar lid with a clean cloth, then pick out a jar lid from the hot water, place it firmly in place on the jar, hand tighten the jar ring onto the lid and place in cold water that comes up about 3/4 of the height of your jars. MAKE SURE the jars don't touch each other in the canner.
Afix the canner's lid on firmly. The way ours works is a counter weight pops up when the water reaches the correct boiling pressure.
Don't let the canner scare you. They all have over pressure relief valves (ours looks like a flat rubber plug). I've never had the over pressure valve blow open on me.
I never add lemon juice, salt or anything to the tomatoes. Never had a problem with them. That way, you can use them in any recipe and not worry about amounts of recipe ingredients.
I've often found quarts of tomato juice/puree that were canned 4-5 years ago, and if the lid "POPS" when you take it off (I always use my fingernail and not a bottle opener. The bottle opener, even being very careful, can easily cause a chip or divit in the jar's sealing surface).
Then I look at the color of the contents and smell it. IF anything seems off, we throw it out. It does occasionally happen, but usually it's because the seal leaked due to a chip on the sealing surface of the canning jar.
Ball's canning guide is nice, and if you have a University nearby, they usually will have an agricultural type department that will have free literature for preserving foods, including canning.
Freezing is ok if time is not important. Canning keeps stuff fresher, longer, and without refrigeration/freezer electricity costs. And never any freezer burn!