Wow, this board has been like a trip down memory lane; thanks for the link! I liked Wood Workshop, it used to be available on TGC. Looks like they have some decent looking seamless textures on their site as well.
Another fun utility was Texture Maker. Don't know if that's still around. Perhaps I'll look around for it later.
EDIT: Wow, it's still around but hasn't been updated in a decade. They are also asking a lot more for it than I paid originally!
Desktop: i7 4770@3.4Ghz (passmark 9809), 12GB RAM, Win 10/64, GeForce GTX 1080 (passmark 12006), 1TB SSD, 1TB HDD; Laptop: i7 4800MQ@2.7Ghz, 16GB RAM, Win 10/64, GeForce GTX870M , 1TB SSD.