I picked Seamless Textures you can Really Use by Tom Marlin. Let's see what old Tom puts on his own disk. This one looks like it might be the original texture disk. An eclectic mix of textures are arranged in alphabetical categories from carpets, clouds and concretes, to stucco, stones and tiles, to wallpaper, windows and wood. A little bit of everything.
Graphics come in large and small sizes, in jpeg format.
Tom says his graphics may be used in your project royalty free. In the gallery directory, I found a number of interesting examples of textures put to good use in full-screen pictures. I could look at this stuff all day. Like I said before, I'm not an artist. But I use a lot of art in my programs, web pages and printed materials, and sometimes I hire artists.