just go on google, and look up texture stock. I found this site, although I'm not too sure it's good (i just clicked the first link), so yeah maybe check out here: http://www.textureking.com/ . Also, just google texture stock, and go to images. That's how I found my mermaid shell texture. But yeah, like Lucien said, your texture can be anything. I mean, the wood background in the sig LT made you is a perfect texture stock. Just try and find something that is sort of a repeated pattern, and not something that's definite, if you know what i mean.