Wow!!
Very cool stuff and great finds!
I'm gonna do some research for you on a few of those items and I'll browse through some of my books and maps and see if I can pinpoint some unit locations for where those items were found.
The 13 star button I would say is obviously Confederate just for the fact that it does have 13 stars although I guess it could be some kind of state militia or issue button as well. I'm no expert on buttons but there should be a bunch of information out there. I will certainly look through some of my books and see what info I can dig out. No pun intended.

The trigger and trigger guard is most certainly from a Springfield model or Springfield pattern rifle. Either an 1842, 1855, 1861 or 63. One of the locks (the second) is an Enfield pattern. The long tear drop one I'm not so sure of offhand but I should be able to figure that one out quite easily with a tiny bit of research.
Just very very cool all around and thanks for sharing this stuff with us!!