It depends as you say, on how much effort you are willing to go to...I usually start them early, but it does not always work out better...
I started early this year with plants in the unheated greenhouse in gallon pots, they were starting to fruit and flower when I planted them out in early April, but that turned out to be too early for this year, as they just sat there for a long time without growing. Only in late August did they really get going, and we have tom's a plenty right now.
On the other hand some cherry tomatoes I direct sowed back in late May did much better - way too well in fact...

So in my experience, I would say that tomatoes which get exposed to sustained cold weather suffer a major setback in long term growth....If you start seeds indoors too early, they will out grow the containers and not be good transplants...so it's a yearly guessing game.. hedge your bets by doing some early, and others later.

A local professional grower (Watsonville) always waits until April to start Tomatoes...

Chad South Bay area

I believe that it would be pretty costly to attempt growing tomatoes in the winter. Lots of equipment to grow them indoors, which is what it sounds like what you want to do.

I hate to be dicouraging, because when folks discourage me, I usually get more determined.
Now I try to go with the flow of the seasons and buy tomatoes now to can or freeze for winter eating.

You know you can just wash tomatoes and pop them into a freezer bag. When you thaw them the skins just peel off and you can make spaghetti sauce or other stuff. Also there are some neat article online for oven dried tomatoes you preserve in Olive oil with sliced garlic. Yum!

Here is a link that might be useful: Madera County Gardening Examiner

I've only got one year's worth of experience, but I can tell you what I did and what I'll do differently next year. I started mine indoors last year around mid-March with the anticipation I would plant them in the yard mid-May. I started 6 of each variety with the intention to end up with 2 each. I got 6 each! LOL But that was okay, because I gave the extras to friends and family.

Next year, I will start mine a little earlier. Probably mid-February to give them a solid 90 days before planting. The 60 day time period didn't get them big enough (barely 6") and I think that's because I don't keep them in a heated environment while growing. I kept them under lights (just regular shop lights very close to the plants), but grew them in my garden shed which isn't heated. Thus, they were a little slower to grow.

I also won't be in a hurry to put them out. I was told and now I believe it: You can put them out early, but they aren't going to do anything until the weather is right for them. I think Chad is right about stressing them by putting them out too early. It's also good advice to maybe try some different things and see what works best for you.

The biggest lesson I learned is that I'm not going to get it right the first year, and probably not even the second or third. I've given up to the fact that I need to experiment and keep adjusting until I find out what works for me, because like you, I've got certain conditions I have to deal with (i.e., not much space in my house and no plans to buy a heated greenhouse any time soon).

Hope that helps!

All this helps a lot! No, I'm not trying to do winter gardening - other than hoping my lettuce/swiss chard/spinach can continue. I just don't have the space/time/resources for such an undertaking although I would love fresh tomatoes in winter.

But, all the advice about starting tomatoes in spring is really helpful - especially the low maintenance ways. We do have a couple places that I could do grow lights on shelves in the garage - if the hubby can give the space. We'll see. Althought the location would be colder than desired but maybe I could plastic it in a little to retain warmth. We'll see - all the suggestions I can get are appreciated!

I live in the Sonoma Valley, climate much like yours. You should start tomatoes indoors 8 weeks before you put them in the ground. The last two weeks you would have transplanted them into little 4" pots so you could acclimate them and move them around as needed.

May 1 is a safe date to put the plants out, and it is not too late. April 15 often works, sosmetimes not. I would not wait any longer than May 15. Plants can be covered for a few nights with cloth or jugs if you encounter one or two cold nights. Only a freeze will kill them.

I gave up starting seeds since I have a local nursery with a wide assortment of tomatoes, and I can find all kinds. It's not worth the effort for me.

As to starting them, it' easy. You can buy a two tube, 48" long flourescent fixture at Home Depot for around $20. Suspend it above the work bench so that the seedlings are just an inch or two from the lights. This will provide warmth as well as light.

Good luck.

RB

What I do to help heat my seedlings is I have two of those seedling heat mats. They're the size of one flat, or you can get them big enough to fit two flats. They were about $20 each through Amazon.com. I turn the heat mats on and let them run all night with the flats covered in a plastic dome to contain the warmth. That raises the evening temperature a little since my shed is unheated. I turn them off during the day because--as you know--around here we can get an 85 degree day in February without warning.

Also, once they outgrow the space from the fluorescents (and I use what Bob uses) I bring the flats out during the day for sunshine, placing them against an east-facing wall where they'll get full sun until around 1:00, then shade after that. That way, if it gets hotter than I expected while I'm at work, I don't have to worry about them frying.
I bring them in at night and set them on the heat mats.

It sounds like a lot of work, but it's not really. I have the mats on a timer so it's just a matter of setting them out and bringing them in. And since I adore checking on my little darlings all the time, it's not really much trouble. ;-)