Tileable textures of red earth and gravel, sticks and dead grass, sand and small weeds. I photographed these textures near the National Museum of Australia, Canberra (right here: https://goo.gl/maps/rFNJJ ). They were cropped and made seamless in the GIMP using Map - Resynthesize. Final textures are 2048x2048 in PNG format.

Synthetic normal maps were generated using the Insane Bump plugin for the GIMP - I tweaked the settings to try and make reasonable maps, but if you think you can do better by all means go ahead !

For my own future reference - preview image was generated using ImageMagick like:

$ montage *.png -geometry 256x256+2+2 -tile 4x6 arid_ground_preview.jpg

(To keep the normal map archive under the 200 Mb limit, I removed two of the sand normal maps - you could easily regenerate these with Insane Bump, or just use one of the other sand maps and it's unlikely anyone will notice :) ).