hi Cris!

to THP!
I just saw this post, thankfully SmokenFire got you headed in the right direction.
There are different directions you can go with how/where/who does the processing. This may be a little disjointed, but I'll try to share what we decided and why.
When I started making and selling salsa...(as my son would say...back in the Dark Ages of 1994....

)...I was making a canned (BWB) salsa. At the time, it was a real PITA to get testing done and no resources to find info about food processing or food testing. The one place I knew of to do food testing like pH, process reviews, shelf life, etc, was the food science department at WSU. Their customer service was HORRIBLE, like taking 4-6 months for a pH test and process review. Regs at the time said that if a product had a pull date of 30 days or less, it was considered a 'fresh' product and wasn't subject to all the shelf stable, shelf life, canned product regs. So that's what I went with- fresh refrigerated.
For your venture-
first and foremost...MAKE SURE people other than friends and family like the salsa. When Scott Zalkind of Lucky Dog Hot Sauce was developing his hot sauces, he would take unlabeled bottles to parties/bbqs/etc and set them out on the table and then hang around and listen to people's comments. Great way to get honest feedback as friends and family may not give you honest feedback not wanting to hurt your feelings.
Another way is to offer 'free' samples to people on here in return for feedback. I say 'free' because you cannot sell your sauce until legally licensed, but most of us here have no problem posting back a few bucks to cover shipping/ jars etc. Getting feedback from people around here will give you some very good feedback. Someone recently posted a thread about what questions to put in a sauce questionnaire. It should be pretty easy to find~
Anyway, when you are SURE you have the perfect recipe, the next steps are to send a sample to a food lab for a process review and also get in contact with the (Dept of Ag??? I think???) or whoever does local food processing licensing in Cali. It is usually NOT your local health department that does restaurants.
What the food lab says for a process will set out how the salsa can be made. Your sauce may be OK with a boiling water bath, or it may require pressure canning. Either way, you can do both of those processes yourself if you have a facility that will work. Lots of posts about where to look for commercial kitchens to use on a part time basis.
Any type of canning will require you to be Better Process Control School certified. BPCS is just another step, and it costs about $500 and a week of your life, but once you are certified, you can do your own processing. You do not have to use a co-packer.
Last thing on your list should be printing labels, etc. Go ahead and work on label concepts, logos, etc, but do NOT print anything until you are completely licensed and all your ingredients and your label set up is approved by your licensing person. If you mess up on font size, or listing of ingredients, you will have to pitch the whole lot of labels.
I'd encourage you to just make some home-printed labels for the first few batches just to make sure everything is working with your recipes etc.
then consider what and how you want the production done. You can produce it yourself in small batches or use a co-packer.
This is definitely not all-inclusive (business licensing, insurance.....more, more more....) but a basics to get you started. Your local licensing authority should be able to guide you through the first steps.
And finally....the FDA......
do not start jumping through FDA hoops unless your process authority (lab) or your health inspector require it! Some recipes require FDA licensing to be made and sold anytime/anywhere. If you sell ANYTHING across state lines, internet sales and such, you have to be FDA registered. Some sauces that contain critical ingredients like meat or dairy (lots of BBQ sauces contain butter) then you have to be FDA registered.
If your sauce is low risk, and you are only selling within your state (no internet sales), then you probably do not have to deal with FDA registration. Again, rely on your inspector and the food lab for guidance.
Hope this helps and Best of Luck on your fun adventure! Hundreds have done what you are setting out to do. It can be done, you can be successful. Just do it right from the start, have an awesome product, have fun and Love It!
salsalady