soaking/brining?

More or less it's soaking the chicken in salt water. I use water, sea salt, onion, garlic, beer I let it sit for 24 hours minimum. I believe this is also how they treat kosher chickens. It works great specially if you are going to smoke the chicken.
PS I do the same thing for all poultry before I cook it.
Brian

Brining promotes a change in the structure of the proteins in the muscle.  The meat will take on moisture and then when cooked lose moisture at a slower rate than unbrined meat.  I brine alot of chickens prior to smoking and the difference is incredible.  I like using 1 cup kosher salt, 1 cup of dark brown sugar, 1 gallon ice water.

Soaking and brining are two completely different things.  I soak my birds in salted ice water for 24 hours after butchering, but that isn't brining.  I use maybe 1-2 cups of salt for about a 45 gallon soaking barrel, and it's done just to help the meat break down a bit and keep the water colder.  It doesn't add saltiness to the meat.  A brine usually has roughly a cup of salt and a cup of sugar per GALLON, plus other ingredients, and it will absolutely make your meat salty- if that's what you're looking for.  Chickens NEED a soak/rest after being butchered, but they do NOT need a brine, unless you're looking for that in a recipe.

i butchered my first 4 birds yesterday. i put them in the fridge in ziploc freezer bags to rest, but i didn't think to soak them (i rinsed them thoroughly though). i was planning on pulling one out to cook tomorrow night and vacuum sealing the others and putting them in the freezer.

should i go back and soak them or is it really past that point?

as for brining, is that something you do right after processing or before you cook them?

The soak isn't absolutely necessary- I find that it cools them quicker and gets rid of excess blood that may be on/in the meat, but a lot of people skip it too.  So, you don't need to go back and do it now.  As for brining, if you're going to do it, do it right before cooking.