Hi Seth
I used cobble roads/walkways from the Lemax people it comes in rolls and needs a lot of unrolling and stapling down to get flat, I used pre printed road bed which I bought from Trainworld, trees are from China as are the people 1:50 scale but very cheap. for rocks I use a variety of stuff, Foam insulation, and grey tile cement, I also use plaster cloth as and when and paint over it when dry, I only use acrylic paints as the are fairly easy to buy and easy to clean and mix different colours. for the "grass" bed I bought several grass mats from our local shop when they are on special offer, I guess you could use the grass matting from Noch, but that is expensive for what you get. I try to use as much scrap from models to create junk. Also try Model Tech studios for the bits and pieces
I hope I have given you enough food for thought, but I am not very artistic, and I do not have a lot of space.
The attachments are from before stripping out the track and starting again
Happy building