What deere said, its really easy to texture in Google Sketchup, you can literally insert an image from online. You can search up what you want, then add 'Seamless Texture' after it and get some good results. (For Example, 'Concrete Floor Seamless Texture'. Just insert it into Google Sketchup, then paint it onto the surfaces, after that you can right click the surfaces, go to 'texture' then you can reposition the texture on the plane so it properly lines up the way you want it too. It's really easy once you get the hang of it. I used to be terrible at texturing but after learning these tricks in photoshop it's been quite easy. Although I still can't make the textures myself (lol).