After a little bit of digging I found my landscape paint.
Nothing special, something I found at the paint store that was mixed wrong and I got it for $1. This helps to seal the ceiling tile when I start gluing down the grass base and gives a nice earthy look.
Once the base paint dried I got the tracks sprayed with a couple of shades of Rust-Oleum brown.
With a bit of cleaning I had the rails clear of paint and the test loco running nice and smooth! Right after I sprayed the tracks, I wiped most of the paint off the rails with a rag dampened with mineral spirits. Later I used a PERFECT track cleaner to get the residue paint off and polish the railheads and turnouts.
Now I can focus on the backdrop. I think I'm going to start by installing new countersunk screw and puddy over them and fill in the seems. If that works well, I'll start painting the hills and then the clouds.