would love to but nothing has really caught my eye, plus I really want the satisfaction of being able to find one and train it I guess! EDIT: i have thought about buying a ficus though! Since they are good starters, and indoor ones
I'm going to be straight with you here and you may not like it.
The above "satisfaction" statement is basically like saying "I want the satisfaction of being able to drive an over-the-road semi truck" but not being able to drive a stick, or even how a shift works. First things first...
The stuff you 've dug up isn't anything you're going to make into an actual bonsai at least not until your hair starts falling out and/or going gray.. Growing either of those tree out will take a decade or more, if you learn how to care for them. Also Eastern Red Cedar (your first tree growing in the mud and big rocks) is pretty bad material to work with in any case. Doubly so if you have no idea what you're doing.
Commercial nursery material offers the advantage of shaving off more than a few years work in simply containerizing a tree. You can start with more substantial material that will actually offer you the chance to "do bonsai" instead of futzing around for years letting a seedling just grow into workable material.
FWIW, BIGGER material is VASTLY easier to take care of and do bonsai with than tiny, wittle bitty twees. The smaller the tree, the less soil, foliage and trunk you have to work with. They are also extremely difficult for beginners who don't know how to water or do much of anything else. Big trees can take forgetful watering, misguided pruning and a lot of other stuff that's ahead of you.
Miss a watering with a two gallon sized pot and a larger tree, won't make that much difference, more mass and water to lose. Make the same mistake with a tree in a teacup sized pot and the tree is a goner. Overfertilize a big tree a bit, the soil mass can probably handle it. Make a similar mistake with a small tree, you can kill it pretty efficiently as the soil hasn't got any buffer capacity to protect the roots. The list goes on. It takes vastly more skill to grow smaller trees well than large trees.
So I made a post about a tree I dug up wanting to bonsai, it ended up not surviving the transition and I got a few new plants, 2 which survived transplanting in winter and are thriving, and one I dug up from a tip layer which occurred naturally! So I need a ID on two of the trees and help with the transplant shock the one is experiencing! I already watered it with sugar water... Will it die or no? Also the j. Virginiana, is it looking good? When I transplanted that one the top died and I ended up cutting it off and I have been working on reshaping it for the past couple months. Also my white pot is really ugly so ignore it, haha. It's just a nice starting pot I think 
