I want to create a small village as a horror setting for my gaming group and found the Thoumont's buildings but I was wondering what options there were for appropriate ground tiles. I am looking for muddy streets and dark brown or dead grass/foliage. I am not sure if something like that is included in the Thoumont's set or in another. I already have numerous older sets including Hinterland, Himmelveil, dungeon, cave, and castle works but the ground tiles included are not exactly what I was looking for.

What I am aiming for is a darker setting. I was inspired by this picture for the village:

Maybe Wildwood Grove?

There is a kitbash for Dead Fall called Mines that have some dirt/mud tiles without any mine car tracks on them.

There are some dirt path ground tiles in Exterior Works - Hinterlands but the grass surrounding the dirt paths are green. Maybe some bashing on your part to change the grass to look dead.

There are some gravel floor tiles in The Garden that might work.

You might want to take a look here: viewtopic.php?f=5&t=9935&hilit=shadowfell

[and a late submission...]
Printing on colored cardstock can produce the effect you want (e.g. grey or brown for dying grass/soil tiles), as will printing in greyscale or using photoshop (etc.) to change the color pallet on the images.