Well, it would take as long for me to search for webpages on that subject as it would for you, so that part I didn't want to answer on first seeing your post.
Also, phytic acid is not any of the same general categories you've asked about and I have no idea if it is absorbed.
As for acetic and oxalic, yes. "Branched chain" is too broad, perhaps there might be some that are not.
On the title question, the phrase "all organic acids" is vastly too broad. There are millions of them. The answer would be no, not all of them are absorbed.
The main thing that dissuaded me is, why? I guessed that most likely the question draws from a concern, created by some, that somehow the body has a terrible time maintaining correct pH and thus what acids one consumes is very important. This is all wrong, but it is a futile battle to try to discuss. (Some things work out to just banging one's head against the wall and no amount of effort will ever make a dent.)
If that is the concern, then if you wanted you could use Google and search:
site:http://tnation.tmuscle.com "Bill Roberts" alkaline
If that is not your concern, then there is no other practical concern regarding acids in fruits.