Can I add my own textures to solidworks?
3 Answer

Edit Appearance
Advanced
Color/Image
Browse
Open image "All Files"
Save as new.p2m file
Good source of textures
http://www.texturewarehouse.com/gallery/

Yes you can add more texture to you appearance tool box.
You can find the location of them through windows explorer. Can't remember off the top of my head exactly where they are stored.
Any .jpg/bitmap etc can be used as a texture. There was a site i found a while ago but can't think of it right now i will google it! Although i usually just use a saved image from google and then scale appropriately...