Try to find any train shows in the area you're willing to drive to. There's always a parts guy, or a couple guys looking to get rid of everything. With a little luck and patience, you should be able to find what you need. And of course if that fails, you may find something you didn't know you were looking for.
It sounds to me like you might need some weight in the tender (for electrical pickup) and in the engine (for pulling power). The older Jupiter tender (I have one) tends to skew sideways a bit, which bites into the gears and grinds. That's the problem with having the motor in the tender and the driving wheels on the engine.
For deadfall, just use twigs and crap from your nearest tree or bush. Get the new growth, as they'll be the smallest on the tree/bush. If you have a gas oven, put them on a baking sheet and stick them in there overnight. The warmth from the pilot light will dry them out extra well so they'll have less chance of rotting, since new growth is often wet.
Thanks all. "My" section of next year's layout will be even bigger. Someone donated some Rivarossi (AHM) Santa Fe long passenger cars and a combine, so I'll change out the couplers to McHenrys (sorry Bachmann, but they work in Rivarossis better than EZMates) and switch the couplers on an old Bachmann B-Unit to put it behind the A Unit that runs well, and run that on a double loop... Well, that's the plan, anyway. When I settle on a definite track plan, I'll upload the screenshots.