I can homemade salsa every year with tomatoes from our garden and we like ours THICK! so this is what we do...
Once we have boiled out tomatoes to get the skin off...we break the tomatoes into pieces..(chunks) and we do it over a big bowl with a strainer in it to catch the seeds.
This way, you can try to squeeze out the seeds and juice all at once...the tomatoes will always have juice in them, but when tearing them apart, get as much juice as you can out of them, that way, you can seperate the juice itself and can tomato juice for cooking, throw away the seeds, and have chunky salsa and the remained juice in the tomatoes will give the salsa a little juice that it needs to be salsa...and good thing is...if you want more juice at all...just take your bowl of juice and add some while its cooking!!
We can tomato juice, tomato chunks, and salso every year!!
Hope this helps!