In yesterday's Wednesday HDR post of Mt. Cotopaxi, Ecuador with an added texture, I suggested you go out and shoot your own textures and experiment with them in Photoshop. Thought I'd show you an example. This is a photo of the docks at Windhoek, Namibia:
This is just some random, ordinary wall I shot in Riga, Latvia:
Here they are, combined in Photoshop:
This was one of my early efforts with textures and it surely will never win any awards, but it also didn't cost $100 - $400, and I learned a whole lot in the process. Just get out there and try it for yourself.