Here are a few high resolution photos of some wood textures. Some of these are great for adding a grunge feel to your work or creating a nice distressed background. There are also several shots of planks of wood that can be easily made into seamless backgrounds.
These photos where all taken with a professional digital SLR camera and are huge files.
If anyone wants to make a photoshop brush pack out of them, I would love to see it.
Here are a few samples of the included photos: